PEPTIDE-UREA DERIVATIVE, PHARMACEUTICAL COMPOSITION CONTAINING SAME AND APPLICATION THEREOF

Abstract

A peptide-urea derivative, a pharmaceutical composition containing same and an application thereof are provided, the derivative being as shown in formula I. The derivative can be used for preoperative imaging diagnosis and grading of PSMA-positive prostate cancer, and can also be used for the treatment of various types and stages of prostate cancer, achieving the integration of diagnosis and treatment, and having broad application prospects.

##STR00001##

Claims

1. A peptide-urea derivative of formula I, or a pharmaceutically acceptable salt thereof; ##STR00112## wherein: L is ##STR00113## wherein the N atom is linked to R; R is a group containing a radioactive metal ion, which is composed of a radioactive metal ion and a group with the function of chelating a metal ion, wherein the radioactive metal ion is chelated with the group with the function of chelating a metal ion, and the group with the function of chelating a metal ion is ##STR00114## ##STR00115##

2. The peptide-urea derivative of formula I according to claim 1, or a pharmaceutically acceptable salt thereof, characterized by meeting one or more of the following conditions: (31) the radioactive metal ion is a radioactive metal ion releasing , or rays; (33) the radioactive metal ion has one or more of the following effects: 1. tracking; 2. delivery; 3. imaging; 4. treatment.

3. The peptide-urea derivative of formula I according to claim 2, or a pharmaceutically acceptable salt thereof, characterized by meeting one or more of the following conditions: (32) the radioactive metal ion has one or more of the following effects: 1. PET imaging; 2. SPECT imaging; 3. radiation treatment.

4. The peptide-urea derivative of formula I according to claim 2, or a pharmaceutically acceptable salt thereof, characterized by meeting one or more of the following conditions: (4) the radioactive metal ion is .sup.68Ga, .sup.89Zr, .sup.64Cu, .sup.86Y, .sup.99mTc, .sup.111In, .sup.90Y, .sup.67Ga, .sup.177Lu, .sup.211At, .sup.153Sm, .sup.186Re, .sup.188Re, .sup.67Cu, .sup.212Pb, .sup.225Ac, .sup.213Bi, .sup.223Ra, .sup.212Bi or .sup.212Pb.

5. The peptide-urea derivative of formula I according to claim 4, or a pharmaceutically acceptable salt thereof, characterized by meeting one or more of the following conditions: (3) the group with the function of chelating a metal ion is ##STR00116## (4) the radioactive metal ion is .sup.68Ga.sup.3+, .sup.89Zr.sup.4+, .sup.64Cu.sup.2+, .sup.86Y.sup.3+, .sup.99mTc.sup.4+, .sup.111In.sup.3+, .sup.90Y, .sup.67Ga.sup.3+, .sup.177Lu.sup.3+, .sup.211At, .sup.153Sm .sup.186Re, .sup.188Re, .sup.67Cu.sup.2+, .sup.212Pb.sup.2+, .sup.225Ac.sup.3+, .sup.213Bi.sup.3+, .sup.223Ra, .sup.212Bi or .sup.212Pb.sup.2+.

6. The peptide-urea derivative of formula I according to claim 1, or a pharmaceutically acceptable salt thereof, characterized in that the peptide-urea derivative of formula I is a compound formed by chelation of compound A and .sup.68Ga.sup.3+, wherein the structure of compound A is as shown in any of the following structures: ##STR00117## ##STR00118##

7. The peptide-urea derivative of formula I according to claim 1, or a pharmaceutically acceptable salt thereof, characterized in that the peptide-urea derivative of formula I is a compound formed by chelation of compound A and .sup.177Lu.sup.3+, wherein the structure of compound A is as shown in any of the following structures: ##STR00119## ##STR00120##

8. The peptide-urea derivative of formula I according to claim 1, or a pharmaceutically acceptable salt thereof, characterized in that the structure of the peptide-urea derivative of formula I is as shown in the following structures: ##STR00121##

9. A pharmaceutical composition, which comprises substance X and pharmaceutical adjuvant; wherein the substance X is the peptide-urea derivative of formula I according to claim 1, or a pharmaceutically acceptable salt thereof.

10. The pharmaceutical composition according to claim 9, wherein the pharmaceutical adjuvant is selected from one or more of DTPA, ascorbic acid, sodium ascorbate and water.

11. A pharmaceutical composition, which comprises substance X and pharmaceutical adjuvant; wherein the substance X is the peptide-urea derivative of formula I according to claim 6, or a pharmaceutically acceptable salt thereof.

12. The pharmaceutical composition according to claim 11, wherein the pharmaceutical adjuvant is selected from one or more of DTPA, ascorbic acid, sodium ascorbate and water.

13. A pharmaceutical composition, which comprises substance X and pharmaceutical adjuvant; wherein the substance X is the peptide-urea derivative of formula I according to claim 7, or a pharmaceutically acceptable salt thereof.

14. The pharmaceutical composition according to claim 13, wherein the pharmaceutical adjuvant is selected from one or more of DTPA, ascorbic acid, sodium ascorbate and water.

15. A pharmaceutical composition, which comprises substance X and pharmaceutical adjuvant; wherein the substance X is the peptide-urea derivative of formula I according to claim 8, or a pharmaceutically acceptable salt thereof.

16. The pharmaceutical composition according to claim 15, wherein the pharmaceutical adjuvant is selected from one or more of DTPA, ascorbic acid, sodium ascorbate and water.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0151] FIG. 1 shows the cell binding test of effect example 5.

[0152] FIG. 2 shows the cell endocytosis test of effect example 5.

[0153] FIG. 3 shows the PET/CT scanning after administration of effect example 6.

[0154] FIG. 4 shows the specificity test of the E series compounds of effect example 6.

[0155] FIG. 5 shows the test result of Log P of effect example 6.

[0156] FIG. 6 shows the test result of binding to PPB of effect example 8.

[0157] FIG. 7 shows the tissue distribution of .sup.177Lu-E3 in various organs of normal SD rats in effect example 9.

[0158] FIG. 8 shows the tissue distribution of .sup.177Lu-E3 in various organs of 22RV1 tumor-bearing mice in effect example 9.

[0159] FIG. 9 shows the SPECT imaging of .sup.177Lu-PSMA-617 of effect example 10.

[0160] FIG. 10 shows the SPECT imaging of .sup.177Lu-E3 of effect example 10.

[0161] FIG. 11 shows the SPECT imaging of .sup.177Lu-E4 of effect example 10.

[0162] FIG. 12 shows the SPECT imaging of .sup.177Lu-E8 of effect example 10.

[0163] FIG. 13 shows the SPECT imaging of .sup.177Lu-E16 of effect example 10.

[0164] FIG. 14 shows the SPECT imaging of .sup.177Lu-E18 of effect example 10.

[0165] FIG. 15 shows the SPECT imaging of .sup.177Lu-E24 of effect example 10.

[0166] FIG. 16 shows the body weight changes of animals in the pharmacodynamic study of .sup.177Lu-E3 in effect example 11.

[0167] FIG. 17 shows the changes in tumor size in the pharmacodynamic study of .sup.177Lu-E3 in effect example 11.

DETAILED DESCRIPTION OF THE EMBODIMENTS

[0168] The present disclosure is further illustrated below by means of examples, but the present disclosure is not limited to the scope of the examples. For the experimental methods that do not emphasize specific conditions in the following examples, the methods and conditions are selected based on conventional methods and conditions, or based on the instructions of commercial products.

Synthesis of Intermediate Compound M1

[0169] ##STR00048##

[0170] General synthetic method A: Fmoc-Lys(Dde)-Wang resin (0.3 mmol/g) was used as a raw material, and added into a reaction vessel. 25% piperidine/DMF (volume ratio) was then added, and the mixture was stirred for 30 min. Ninhydrin detection showed dark blue. The reaction solution was dried by suction, filtered, and washed 5 times with DMF. The N-terminal Fmoc protecting group was removed to make the N-terminal a free amino group; DMF was used as a solvent, and N,N-disuccinimidyl carbonate (1 equivalent), N,N-diisopropylethylamine DIPEA (2 equivalent) and 4-dimethylaminopyridine DMAP (2 equivalent) were added in a proportion (1:2:2). The mixture was reacted under the protection of nitrogen for 1 h. H-Glu(OtBu)-OH (1.1 equivalent) was then added, and the mixture was stirred for 24 hours. The Dde protecting group of the side chain of Lys was then removed with 2% hydrazine hydrate/DMF solution, and then Fmoc-2-Nal-OH/HOBt/DIC (3 equivalents) was added to graft the resin to introduce 2-Nal amino acid residue. Subsequently, 25% piperidine/DMF (volume ratio) was used to remove the Fmoc protecting group again so that the N-terminus of 2-Nal became a free amino group, and the product M1 was synthesized.

The Synthetic Method of Intermediate Compound M2:

[0171] ##STR00049##

Synthesis of Intermediate M2-2:

[0172] Compound M2-1 (250 mg, 1.29 mmol), and TMSCH.sub.2N.sub.2 (445 mg, 3.86 mmol) were added dropwise to MeOH (10 ml), and the reaction mixture was stirred at room temperature in a 100 mL round bottom flask for 2 hours. LCMS monitored the completion of the reaction. The reaction mixture was poured into water (50 mL) to quench the reaction, and the mixture was extracted with ethyl acetate (50 mL3). The organic phases were combined. The combined organic phase was washed with saturated sodium chloride (50 mL1), dried over sodium sulfate, and filtered. The filtrate was concentrated. The crude product was purified by a thick preparative plate to give the compound M2-2 (200 mg, 74.6%).

Synthesis of Intermediate M2-3:

[0173] Compound M2-2 (200 mg, 0.96 mmol), HATU (2-(7-azabenzotriazole)-N,N,N,N-tetramethyluronium hexafluorophosphate) (437 mg, 1.15 mmol) and DIEA (N,N-diisopropylethylamine) (247 mg, 1.92 mmol) were added to DCM (5 mL), and the reaction was stirred at room temperature in a 100 mL round bottom flask for 5 min. Compound DOTA (549 mg, 0.96 mmol) was then added, and the reaction mixture was stirred at this temperature for another 1 h. LCMS monitored the completion of the reaction. The reaction mixture was poured into water (50 mL) to quench the reaction, and the mixture was extracted with DCM (50 mL3). The organic phases were combined. The combined organic phase was washed with saturated sodium chloride (50 mL1), dried over sodium sulfate, and filtered. The filtrate was concentrated. The crude product was purified by a thick preparative plate to give the compound M2-3 (500 mg, 68.23%).

Synthesis of Intermediate M2:

[0174] Compound M2-3 (500 mg, 0.655 mmol) and LiOH (32 mg, 1.31 mmol) were added to MeOH (8 ml)/H.sub.2O (2 mL), and the reaction was stirred at room temperature in a 100 mL round bottom flask for 2 hrs. LCMS monitored the completion of the reaction. The reaction mixture was poured into water (50 mL) to quench the reaction, and the mixture was extracted with EtOAc (50 mL3). The organic phases were combined. The combined organic phase was washed with saturated sodium chloride (50 mL1), dried over sodium sulfate, and filtered.

[0175] The filtrate was concentrated. The crude product was purified by a thick preparative plate and then purified by pre-HPLC to give the compound M2 (60 mg, 12.2%); .sup.1H NMR (400 MHz, DMSO-d.sub.6) 13.13-12.51 (brs, 1.0H), 8.24 (d, J=1.2 Hz, 1H), 8.04 (d, J=8.3 Hz, 1H), 7.84 (dd, J=8.3, 1.5 Hz, 1H), 3.42 (d, J=16.5 Hz, 8H), 2.94-2.66 (m, 17H), 1.31 (s, 27H). LCMS: [M1].sup.+=747.4

[0176] The following intermediates were synthesized by the synthetic method of the above-mentioned intermediate M2:

##STR00050##

[0177] B3 (820 mg, 28.5%) was obtained by using the synthetic method of general intermediate M2, MS: [M+1].sup.+=683.5.

##STR00051##

[0178] B4 (568 mg, 35.8%) was obtained by using the synthetic method of general intermediate M2, MS: [M+1].sup.+=683.5.

##STR00052##

[0179] B6 (768 mg, 39%) was obtained by using the synthetic method of general intermediate M2, MS: [M+1].sup.+=683.5.

##STR00053##

[0180] B11 (368 mg, 26%) was obtained by using the synthetic method of general intermediate M2, MS: [M+1].sup.+=683.5.

##STR00054##

[0181] B17 (612 mg, 29.9%) was obtained by using the synthetic method of general intermediate M2, MS: [M+1].sup.+=683.5.

##STR00055##

[0182] B18 (712 mg, 30.9%) was obtained by using the synthetic method of general intermediate M2, MS: [M+1].sup.+=683.5.

##STR00056##

[0183] B23 (568 mg, 37.9%) was obtained by using the synthetic method of general intermediate M2, MS: [M+1].sup.+=683.5

##STR00057##

[0184] B24 (658 mg, 45.9%) was obtained by using the synthetic method of general intermediate M2, MS: [M+1].sup.+=761.1

Synthesis of Intermediate Compounds Protected by Fmoc

[0185] General synthetic method B: Compound Fomc-Osu (1 equivalent) and amino-containing compound (1 equivalent) were dissolved in 1,4-dioxane (4 mL) and water (2 mL), and sodium carbonate (1.85 equivalent) was added. The mixture was stirred at room temperature for 10 h. TLC result showed that the raw materials were consumed completely. The solvent was removed by suction under reduced pressure. The pH was adjusted to 3-4 by adding 0.1 mol/L NH.sub.4Cl solution, and the mixture was extracted twice with EtOAc. The organic phase was dried and concentrated, and the crude product was purified by pre-HPLC to give the corresponding Fmoc-protected compound.

##STR00058##

[0186] M3 was obtained by using general synthetic method B (168 mg, 57.9%); .sup.1H NMR (400 MHz, DMSO-d.sub.6) 12.08 (s, 1H), 7.89 (d, J=7.5 Hz, 2H), 7.63 (d, J=7.4 Hz, 2H), 7.42 (t, J=7.3 Hz, 2H), 7.34 (td, J=7.4, 0.9 Hz, 2H), 4.31 (d, J=6.7 Hz, 2H), 4.23 (t, J=6.7 Hz, 1H), 3.50 (d, J=17.9 Hz, 4H), 2.16 (s, 1H), 1.75 (t, J=10.3 Hz, 4H), 1.39 (ddd, J=28.9, 17.8, 6.8 Hz, 4H); LCMS: [M1].sup.+=390.2.

##STR00059##

[0187] Compound M4 (107 mg, 97.7%) was obtained by using general synthetic method B; .sup.1H NMR (400 MHz, DMSO-d.sub.6) 13.18-12.22 (m, 1H), 7.78 (dd, J=76.9, 28.8 Hz, 6H), 7.46-7.16 (m, 5H), 4.54 (s, 2H), 4.42 (d, J=6.2 Hz, 2H), 4.31 (t, J=6.2 Hz, 1H), 3.52 (s, 2H), 2.75 (s, 2H); LCMS: [M1].sup.+=398.1.

##STR00060##

[0188] Compound M5 (150 mg, 98.2%) was obtained by using general synthetic method B; .sup.1H NMR (400 MHz, DMSO-d.sub.6) 12.45-11.54 (m, 1H), 7.90 (d, J=7.5 Hz, 2H), 7.63 (d, J=7.4 Hz, 2H), 7.41 (d, J=7.4 Hz, 2H), 7.35 (dd, J=7.4, 0.7 Hz, 2H), 4.39 (d, J=6.3 Hz, 2H), 4.27 (d, J=6.2 Hz, 1H), 3.28-3.19 (m, 4H), 2.16 (ddd, J=14.8, 7.5, 3.8 Hz, 1H), 1.63 (ddd, J=23.0, 12.6, 8.8 Hz, 4H), 1.513-1.421 (m, 2H), 1.28-1.05 (m, 6H); LCMS: [M1].sup.+=418.2.

##STR00061##

[0189] Compound M6 (168 mg, 57.91%) was obtained by using general synthetic method B; .sup.1H NMR (400 MHz, DMSO-d.sub.6) 11.99 (s, 1H), 7.88 (d, J=7.5 Hz, 2H), 7.69 (d, J=7.3 Hz, 2H), 7.41 (t, J=7.2 Hz, 2H), 7.32 (t, J=7.0 Hz, 2H), 7.02 (s, 1H), 4.19 (s, 3H), 1.75 (s, 12H); LCMS: [M1].sup.+=390.1.

##STR00062##

[0190] Compound M7 (121 mg, 98.7%) was obtained by using general synthetic method B; .sup.1H NMR (400 MHz, DMSO-d.sub.6) 8.08 (s, 1H), 7.88 (d, J=7.5 Hz, 2H), 7.67 (d, J=7.1 Hz, 2H), 7.41 (t, J=7.4 Hz, 2H), 7.33 (td, J=7.4, 1.0 Hz, 2H), 4.24 (d, J=27.0 Hz, 3H), 2.08 (t, J=18.1 Hz, 5H), 1.58 (s, 1H), 1.23 (s, 1H); LCMS: [M1].sup.+=348.2.

##STR00063##

[0191] Compound M8 (151 mg, 89.9%) was obtained by using general synthetic method B; .sup.1H NMR (400 MHz, DMSO-d.sub.6) 11.99 (s, 1H), 7.88 (d, J=7.5 Hz, 2H), 7.69 (d, J=7.3 Hz, 2H), 7.41 (t, J=7.2 Hz, 2H), 7.32 (t, J=7.0 Hz, 2H), 7.02 (s, 1H), 4.19 (s, 3H), 2.89 (d, J=2.7 Hz, 2H), 1.75 (s, 12H); LCMS: [M1].sup.+=404.2.

##STR00064##

[0192] Compound M9 (110 mg, 56.7%) was obtained by using general synthetic method B; .sup.1H NMR (400 MHz, DMSO-d.sub.6) 8.08 (s, 1H), 7.88 (d, J=7.5 Hz, 2H), 7.67 (d, J=7.1 Hz, 2H), 7.41 (t, J=7.4 Hz, 2H), 7.33 (td, J=7.4, 1.0 Hz, 2H), 4.24 (d, J=27.0 Hz, 3H), 2.99 (d, J=2.7 Hz, 2H) 2.08 (t, J=18.1 Hz, 5H), 1.58 (s, 1H), 1.23 (s, 1H); LCMS: [M1].sup.+=362.2.

##STR00065##

[0193] Compound M10 (1155 mg, 63.3%) was obtained by using general synthetic method B; .sup.1H NMR (400 MHz, DMSO-d.sub.6) 13.18-12.22 (m, 1H), 7.78 (dd, J=76.9, 28.8 Hz, 6H), 7.46-7.16 (m, 5H), 4.54 (s, 2H), 3.17 (d, J=1.37 Hz, 2H), 2.75 (d, J=6.2 Hz, 2H), 2.73 (t, J=6.2 Hz, 2H), 1.99 (m, 1H).

##STR00066##

[0194] Compound M11 (165 mg, 86.7%) was obtained by using general synthetic method B; MS: [M1].sup.+=398.2.

##STR00067##

[0195] Compound M12 (210 mg, 76.5%) was obtained by using general synthetic method B; MS: [M1].sup.+=404.2.

##STR00068##

[0196] Compound B8 (820 mg, 65%) was obtained by using general synthetic method B; 1H NMR (400 MHz, CDCl.sup.3) 7.77 (d, J=7.6 Hz, 2H), 7.61 (d, J=7.6 Hz, 2H), 7.37 (t, J 7.6 Hz, 2H), 7.28 (t, J=7.6 Hz, 2H), 4.31-4.45 (m, 2H), 4.18-4.22 (m, 1H), 3.68-3.75 (m, 1H), 3.61-3.71 (m, 1H), 3.48-3.58 (m, 2H), 2.16-2.21 (m, 2H), 1.45-1.48 (m, 1H). MS: [M+1].sup.+=350.1.

##STR00069##

[0197] Compound B12 (210 mg, 76.5%) was obtained by using general synthetic method B; .sup.11HNMR (400 MHZ, DMSO-d.sub.6) 12.02 (s, 1H), 7.89 (d, J=7.6 Hz, 2H), 7.62 (d, J=7.6 Hz, 2H), 7.41 (d, J=7.6 Hz, 2H), 7.33 (d, J=7.6 Hz, 2H), 4.33-4.52 (m, 2H), 4.22-4.31 (m, 1H), 3.18-3.25 (m, 4H), 2.02-2.21 (m, 1H), 1.16-1.68 (m, 12H). MS: [M+1].sup.+=420.

##STR00070##

[0198] Compound B16 (300 mg, 79%) was obtained by using general synthetic method B, MS: [M+1].sup.+=401.1.

##STR00071##

[0199] Compound B19 (300 mg, 80%) was obtained by using general synthetic method B, .sup.1H NMR (400 MHz, DMSO-d.sub.6) 12.71 (s, 1H), 7.91 (d, J=8.0 Hz, 2H), 7.65 (d, J=8.0 Hz, 2H), 7.42 (t, J=12 Hz, 2H), 7.33 (t, J=8.0 Hz, 2H), 7.21 (br s, 1H), 4.69 (d J=8.0 Hz, 2H), 4.35 (s, 1H), 3.49-3.56 (m, 2H), 2.52-2.77 (m, 2H), 1.65-1.79 (m, 2H), MS: [M+1].sup.+=400.1.

##STR00072##

[0200] Compound B20 (450 mg, 79%) was obtained by using general synthetic method B, 1H NMR (400 MHz, DMSO-d.sub.6) 12.99 (s, 1H), 9.88 (s, 1H), 7.21-8.02 (m, 16H), 4.30-4.61 (m, 2H), 4.25-4.30 (m, 1H); MS: [M+1].sup.+=436.2.

##STR00073##

[0201] Compound B21 (500 mg, 87%) was obtained by using general synthetic method B. 1H NMR (400 MHz, DMSO-d.sub.6) 12.92 (s, 1H), 10.12 (s, 1H), 8.5 (s, 1H), 8.13 (s, 1H), 7.71-8.12 (m, 4H), 7.50-7.69 (m, 1H), 7.30-7.49 (m, 4H), 4.45-4.58 (m, 2H), 4.31-4.40 (m, 1H); MS: [M+1].sup.+=410.2.

##STR00074##

[0202] Compound B22 (300 mg, 75%) was obtained by using general synthetic method B. .sup.1H NMR (400 MHZ, DMSO-d.sub.6) 12.11 (br s, 1H), 7.89 (d, J=7.5 Hz, 2H), 7.68 (d, J=7.3 Hz, 2H), 7.42 (t, J=7.2 Hz, 2H), 7.33 (t, J=7.0 Hz, 2H), 4.22-4.33 (m, 3H), 3.90 (s, 2H), 3.80 (s, 2H), 2.82-2.95 (m, 1H), 2.25-2.41 (m, 4H). MS: [M+1].sup.+=364.3.

##STR00075##

[0203] Compound B25 (620 mg, 67%) was obtained by using general synthetic method B, .sup.1H NMR (400 MHZ, DMSO-d.sub.6) 12.32 (br s, 1H), 10.28 (s, 1H), 9.22 (s, 1H), 8.82 (s, 1H), 8.29 (s, 1H), 8.08 (d, J=9.2 Hz, 1H), 7.92 (d, J=7.6 Hz, 2H), 7.78 (d, J=7.2 Hz, 2H), 7.75-7.76 (m, 1H), 7.44 (t, J=7.2 Hz, 2H), 7.37 (t, J=7.2 Hz, 2H), 4.58 (d, J=6.4 Hz, 2H), 4.36 (t, J=6.8 Hz, 1H). MS: [M+1].sup.+=411.1.

##STR00076##

[0204] Compound B26 (700 mg, 81%) was obtained by using general synthetic method B, MS: [M+1].sup.+=366.2.

[0205] General deprotection step for Fmoc protecting group: A solution of 5% piperidine, 1.25% DBU and 1% HOBt in DMF (v/v/w/v) (approximately 6 mL solution/g resin) was mixed with a resin and stirred at room temperature for 10 minutes. The mixture was filtered, and then the same solution was added and stirred at room temperature for 20 minutes. The mixture was filtered. The resin was then washed in the following order: 2DMF, 2MTBE, 2DMF, and the resin was ready for use after washing.

Example 1. Synthesis of Compound E1

[0206] ##STR00077##

General synthetic method C:
1) Synthesis of intermediate E1-1:

[0207] The resin-loaded compound M1 and compound M2 were added to a reaction flask in an equal equivalent ratio. DMF was used as a solvent, and an equal equivalent of HOBt and DIC were respectively added for resin condensation coupling. The mixture was stirred at room temperature for 2.5 hours. The detection method was ninhydrin detection showing dark blue. After the completion of the reaction by monitoring, the reaction solution was filtered and washed 3-5 times with DMF to give intermediate E1-1, which was directly used in the next step.

2) Synthesis of Compound E1:

[0208] A cleavage reagent (trifluoroacetic acid:H.sub.2O:triisopropylsilane=90:5:5, v/v) was used to cleave the target polypeptide from the compound E1-1 resin and remove the side chain protecting group (cleaving at 30 C. for 3 hours). The filtrate was added to a large amount of cold anhydrous diethyl ether to precipitate the polypeptide, and the mixture was centrifuged. The polypeptide was washed several times with diethyl ether and then dried to give the crude polypeptide. The crude product was purified by reverse-phase high-performance liquid chromatography to give compound E1. Column model: Agela C18 (10 m, 100 , 50250 mm). Chromatographic operating conditions: mobile phase A was an aqueous solution containing 0.05% trifluoroacetic acid and 2% acetonitrile, mobile phase B was 90% acetonitrile aqueous solution, the flow rate was 25 milliliters per minute, and the ultraviolet detection wavelength was 220 nanometers. After freeze-drying the solvent, the pure peptide in a fluffy state was obtained. The chemical structure was characterized by MALDI-TOF mass spectrometry, and the purity was determined by analytical high-performance liquid chromatography (Agela C18-10250 mm, flow rate: 1 ml per minute). MS: [M+2].sup.+=1080.3, [M+Na].sup.+=1102.4.

Example 2. Synthesis of Compound E2

[0209] ##STR00078## ##STR00079##

General Synthetic Method D:

1) Synthesis of Intermediate E2-1:

[0210] The resin-loaded compound M1 and compound M3 (1.5 times the equivalent) were respectively added into a reaction flask. DMF was used as a solvent, and then 1.5 equivalents of HOBt and 1.5 equivalents of DIC were added for resin condensation coupling. The mixture was stirred at room temperature for 2.5 hours. The detection method was ninhydrin detection showing dark blue. After the completion of the reaction by monitoring, the reaction solution was filtered and washed 3-5 times with DMF to give compound E2-1;

2) Synthesis of Intermediate E2-2:

[0211] The intermediate E2-1 was added to a reaction flask, and the Fmoc protecting group was removed with 25% piperidine/DMF (volume ratio). The mixture was then filtered and washed 3-5 times with DMF. The washed and dried compound was added to a reaction bottle containing DMF. 2 times the equivalent of DOTA-Tris (t-Bu) ester, 2 times the equivalent of HOBt and 2 times the equivalent of DIC were added respectively, and stirred at room temperature for 2.0 hours. The detection method was ninhydrin detection showing dark blue. After the completion of the reaction, the reaction solution was filtered and washed 3-5 times with DMF to give intermediate compound E2-3;

3) Synthesis of Compound E2:

[0212] A cleavage reagent (trifluoroacetic acid:H.sub.2O:triisopropylsilane=90:5:5, v/v) was added into a reaction vial containing intermediate E2-3 to cleave the target polypeptide from the resin and remove the side chain protecting group (cleaving at 30 C. for 3 hours). The filtrate was added to a large amount of cold anhydrous diethyl ether to precipitate the polypeptide and the mixture was centrifuged. The polypeptide was washed several times with diethyl ether and then dried to give the crude polypeptide. The crude product was purified by reverse-phase high-performance liquid chromatography to give compound E2. Column model: Agela C18 (10 m, 100 , 50250 mm). Chromatographic operating conditions: mobile phase A was an aqueous solution containing 0.05% trifluoroacetic acid and 2% acetonitrile; mobile phase B was 90% acetonitrile in water; from 0% B to 100% B within 25 minutes. The flow rate was 25 ml per minute and the UV detection wavelength was 220 nm. After freeze-drying the solvent, the pure peptide in a fluffy state was obtained. The chemical structure was characterized by MALDI-TOF mass spectrometry, and the purity was determined by analytical high-performance liquid chromatography (Agela C18-10250 mm, flow rate: 1 ml per minute), wherein mobile phase A was an aqueous solution containing 0.05% trifluoroacetic acid and 2% acetonitrile, and mobile phase B was 90% acetonitrile in water (from 0% B to 100% B within 10 minutes). MS: [M+1].sup.+=1054.6, [M+Na].sup.+=1075.8.

Example 3: Synthesis of Compound E3

[0213] ##STR00080##

[0214] Both of general synthetic method C, D can obtain compound E3; MS: [M+1].sup.+=1062.1, [M+Na].sup.+=1084.7

Example 4: Synthesis of Compound E4

[0215] ##STR00081##

[0216] Compound E4 was obtained by using general synthetic method C.

Example 5: Synthesis of Compound E5

[0217] ##STR00082##

[0218] Compound E5 was obtained by using general synthetic method D; MS: [M+1].sup.+=1027.6, [M+Na].sup.+=1049.8

Example 6: Synthesis of Compound E6

[0219] ##STR00083##

[0220] Both of general synthetic method C, D can obtain compound E6; MS: [M+1].sup.+=1063.5, [M+Na].sup.+=1085.4

Example 7: Synthesis of Compound E7

[0221] ##STR00084##

[0222] Compound E7 was obtained by using general synthetic method D; MS: [M+1].sup.+=1077.2

Example 8: Synthesis of Compound E8

[0223] ##STR00085##

[0224] Compound E8 was obtained by using general synthetic method D; MS: [M+1].sup.+=1013.07

Example 9: Synthesis of Compound E9

[0225] ##STR00086##

[0226] Compound E9 was obtained by using general synthetic method D; MS: [M+1].sup.+=1084.2, [M+Na].sup.+=1105.3

Example 10: Synthesis of Compound E10

[0227] ##STR00087##

[0228] Compound E10 was obtained by using general synthetic method D: MS: [M+1].sup.+=1069.5, [M+Na].sup.+=1090.5

Example 11: Synthesis of Compound E11

[0229] ##STR00088##

[0230] Compound E11 was obtained by using general synthetic method C; MS: [M+1].sup.+=1048.4

Example E12: Synthesis of Compound E12

[0231] ##STR00089##

[0232] Compound E12 was obtained by using general synthetic method D; MS: [M+1].sup.+=1082.5

Example 13: Synthesis of Compound E13

[0233] ##STR00090##

[0234] Compound E13 was obtained by using general synthetic method D; MS: [M+1].sup.+=1055.2, [M+Na].sup.+=1076.5

Example 14: Synthesis of Compound E14

[0235] ##STR00091##

[0236] Compound E14 was obtained by using general synthetic method D; MS: [M+1].sup.+=1013.1, [M+Na].sup.+=1034.4

Example 15: Synthesis of Compound E15

[0237] ##STR00092##

[0238] Compound E15 was obtained by using general synthetic method D; MS: [M+1].sup.+=1069.1, [M+Na].sup.+=1090.5

Example 16: Synthesis of Compound E16

[0239] ##STR00093##

[0240] Compound E16 was obtained by using general synthetic method D; MS: [M+1].sup.+=1063.4

Example 17: Synthesis of Compound E17

[0241] ##STR00094##

[0242] Compound E17 was obtained by using general synthetic method C; MS: [M+1].sup.+=1063.5

Example 18: Synthesis of Compound E18

[0243] ##STR00095##

[0244] Compound E18 was obtained by using general synthetic method C; MS: [M+1].sup.+=1068.6

Example 19: Synthesis of Compound E19

[0245] ##STR00096##

[0246] Compound E19 was obtained by using general synthetic method D; MS: [M+1].sup.+=1063.2

Example 20: Synthesis of Compound E20

[0247] ##STR00097##

[0248] Compound E20 was obtained by using general synthetic method D; MS: [M+1].sup.+=1099.4

Example 21: Synthesis of Compound E 21

[0249] ##STR00098##

[0250] Compound E21 was obtained by using general synthetic method D; MS: [M+1].sup.+=1073.5

Example 22: Synthesis of Compound E22

[0251] ##STR00099##

[0252] Compound E22 was obtained by using general synthetic method D; MS: [M+1].sup.+=1026.5

Example 23: Synthesis of Compound E23

[0253] ##STR00100##

[0254] Compound E23 was obtained by using general synthetic method C; MS: [M+1].sup.+=1014.1

Example 24: Synthesis of Compound E24

[0255] ##STR00101##

[0256] Compound E24 was obtained by using general synthetic method C; MS: [M+1].sup.+=1090.5

Example 25: Synthesis of Compound E25

[0257] ##STR00102##

[0258] Compound E25 was obtained by using general synthetic method D; MS: [M+1].sup.+=1073.5

Example E26: Synthesis of Compound E26

[0259] ##STR00103##

[0260] Compound E26 was obtained by using general synthetic method D; MS: [M+1].sup.+=1029.1

Example 27: Synthesis of Reference Compound PSMA-617

[0261] ##STR00104##

[0262] Compound PSMA-617 was obtained by using general synthetic method D; MS: [M+1].sup.+=1043.1

[0263] The preparation methods and characterizations of all compounds were summarized in Table 1.

TABLE-US-00001 TABLE 1 Synthetic methods and characterizations of compounds Compound Synthetic methods HPLC t.sub.r (min) MS [M + 1].sup.+ E1 C 25.90.sup.3 1080.1 E2 D 12.83.sup.2 1055.1 E3 C, D 11.82.sup.2 1062.5 E4 C 12.45.sup.2 1062.5 E5 D 13.89.sup.2 1013.2 E6 C, D 12.16.sup.2 1049.2 E7 D 7.34.sup.1 1077.2 E8 D 6.17.sup.1 1013.07 E9 D 14.71.sup.2 1083.2 E10 D 13.62.sup.2 1069.2 E11 C 11.47.sup.2 1048.4 E12 D 12.42.sup.2 1082.5 E13 D 11.67.sup.2 1055.2 E14 D 13.89.sup.2 1013.1 E15 D 12.85.sup.2 1069.2 E16 D 10.14.sup.2 1064.1 E17 C 11.36.sup.2 1064.1 E18 C 11.39.sup.2 1068.6 E19 D 12.05.sup.2 1063.2 E20 D 7.63.sup.1 1099.4 E21 D 12.27.sup.2 1073.5 E22 D 9.66.sup.2 1026.5 E23 C 12.11.sup.2 1014.1 E24 C 13.65.sup.2 1090.5 E25 D 9.96.sup.2 1073.5 E26 D 9.78.sup.2 1029.1 PSMA-617 D 12.08.sup.2 1043.1 .sup.1means using LCMS detection method 1

[0264] LCMS detection method 1: the characterization of the compound was carried out by MS, and the purity was determined by an analytical high-performance liquid chromatograph (Agela C18-10250 mm, flow rate: 1 ml per minute), wherein the mobile phase A was an aqueous solution containing 0.05% trifluoroacetic acid and 2% acetonitrile, mobile phase B was 90% acetonitrile in water, the detection wavelength was 220 nm (from 0% B to 100% B in 10 minutes).

[0265] .sup.2 means using LCMS detection method 2

[0266] LCMS detection method 2: the characterization of the compound was carried out by MS, and the purity was determined by an analytical high-performance liquid chromatograph (Agela C18-10250 mm, flow rate: 1 ml per minute), wherein the mobile phase A was an aqueous solution containing 0.05% trifluoroacetic acid and 2% acetonitrile, mobile phase B was 90% acetonitrile in water, (from 0% B to 100% B in 25 minutes).

[0267] .sup.3 means using LCMS detection method 3

[0268] LCMS detection method 3: the characterization of the compound was carried out by MS, and the purity was determined by an analytical high-performance liquid chromatograph (Agela C18-10250 mm, flow rate: 1 ml per minute), wherein the mobile phase A was an aqueous solution containing 0.05% trifluoroacetic acid and 2% acetonitrile, the mobile phase B was 90% acetonitrile in water, (from 8% B to 43% B within 35 minutes), and the detector wavelength was 220 nm.

Example 28: Synthesis of Metal Complex .SUP.177.Lu-E1

[0269] ##STR00105##

General Synthetic Method E:

[0270] 1) 4.1 g of sodium acetate was weighed, and 45 mL of ultrapure water was added. After the sodium acetate was completely dissolved, the pH was adjusted to 4.0 with glacial acetic acid. Additional ultrapure water was added until the total volume was 50 mL to obtain a 1M sodium acetate solution. The metal heating block was turned on and pre-heated to 95 C.

[0271] 2) The precursor compound E1 (1 mg) was weighed respectively, and 1000 L of sodium acetate solution was added respectively. After fully dissolved, a 1 g/L precursor solution was obtained. 10 L (10 g) of the precursor solution was weighed, and then diluted by adding 240 L of sodium acetate solution. Then 250 Ci of .sup.177LuCl.sub.3 solution was added respectively. The mixture was mixed evenly, and then placed in the heating block and reacted at 95 C. for 30 min. Purification was performed using a C.sub.18 Sep-Pak.

[0272] 3) 0.5 g of EDTA sodium salt was weighed, and 50 mL of normal saline was added. The mixture was fully dissolved to obtain a 1% aqueous solution of EDTA sodium salt. 2 L of .sup.177LuCl.sub.3 solution was weighed and spotted on a silica gel plate of instant thin-layer chromatography at a distance of 1 cm from the bottom, and blown dry. 2 L of the reacted solution was weighed and spotted on a silica gel plate of instant thin-layer chromatography at a distance of 1 cm from the bottom, and blown dry. 0.5 mL of 1% EDTA sodium salt solution was used as the developing agent. The bottom of the silica gel plate was placed in the developing agent of the glass test tube, and the bottom of the silica gel plate extended into the liquid level of the developing agent no more than 5 mm. The rubber stopper was covered. When the developing agent was developed to 9-10 cm high on the plate, the silica gel plate was taken out and blown dry. The gamma scanner was used to scan the silica gel plate to compare the .sup.177LuCl.sub.3 solution and the reaction mixture solution. Radiochemical purity and labeling yield were calculated from peak areas.

[0273] As shown in Table 2, the .sup.177LuCl.sub.3 solution was developed to the top of the silica gel plate in the developing agent.

TABLE-US-00002 TABLE 2 Region: .sup.177Lu Detector: PMT Start Finish Rate of Area % ROI % Total Name (mm) (mm) flow (RF) (Counts) (%) proportion (%) Region 1 79.6 97.8 0.988 2284 100.00 95.17 1 peak 2284 100.00 95.17 Total area: 2400 Counts Average background: 0 Counts [0274] Total area: 2400 Counts [0275] Average background: 0 Counts

[0276] As shown in Table 3, the labeled compound .sup.177Lu-E1 can only be developed to the bottom of the silica gel plate in the developing agent. The radiochemical purity was 96.0%, and the labeling rate was also 100%.

TABLE-US-00003 TABLE 3 Region: .sup.177Lu Detector: PMT Start Finish Rate of Area % ROI % total Name (mm) (mm) flow (RF) (Counts) (%) proportion (%) Region 1 10.6 30.8 0.163 2386 100.00 96.91 1 peak 2386 100.00 96.91 Total area: 2462 Counts Average background: 0 Counts

Example 29: Synthesis of Metal Complex .SUP.177.Lu-E2

[0277] ##STR00106##

[0278] Using general synthetic method E, .sup.177Lu-E2 with a radiochemical purity of 97.4% was obtained as shown in Table 4, and the labeling rate was 100%.

TABLE-US-00004 TABLE 4 Region: .sup.177Lu Detector: PMT Start Finish Rate of Area % ROI % Total Name (mm) (mm) flow (RF) (Counts) (%) proportion (%) Region 1 5.2 21.8 0.040 3367 100.00 97.42 1 peak 3367 100.00 97.42 Total Area: 3456 Counts Average background: 0 Counts

Example 30: Synthesis of Metal Complex .SUP.177.Lu-E3

[0279] ##STR00107##

[0280] Using general synthetic method E, .sup.177Lu-E3 with a radiochemical purity of 98.2% was obtained as shown in Table 5, and the labeling yield was 100%.

TABLE-US-00005 TABLE 5 Region: .sup.177Lu Detector: PMT Start Finish Rate of area % ROI % Total Name (mm) (mm) flow (RF) (Counts) (%) proportion (%) Region 1 4.8 20.8 0.033 4420 100.00 98.20 1 peak 4420 100.00 98.20 Total Area: 4501 Counts Average background: 0 Counts

Example 31: Synthesis of Metal Complex .SUP.177.Lu-E9

[0281] ##STR00108##

[0282] Using general synthetic method E, .sup.177Lu-E9 with a radiochemical purity of 98.4% was obtained as shown in Table 6, and the labeling yield was 100%.

TABLE-US-00006 TABLE 6 Region: .sup.177Lu Detector: PMT Start Finish Rate of Area % ROI % Total Name (mm) (mm) flow (RF) (Counts) (%) proportion (%) Region 1 7.2 23.6 0.078 5019 100.00 98.35 1 peak 5019 100.00 98.35 Total area: 5103 Counts Average background: 0 Counts

Example 32: Synthesis of Metal Complex .SUP.177.Lu-E14

[0283] ##STR00109##

[0284] Using general synthetic method E, .sup.177Lu-E14 with a radiochemical purity of 98.5% was obtained as shown in Table 7, and the labeling yield was 100%.

TABLE-US-00007 TABLE 7 Region: .sup.177Lu Detector: PMT Start Finish Rate of Area % ROI % Total Name (mm) (mm) flow (RF) (Counts) (%) proportion (%) Region 1 6.8 25.2 0.080 5697 100.00 98.53 1 peak 5697 100.00 98.53 Total area: 5782 Counts Average background: 0 Counts

Example 33: Synthesis of Metal Complex .SUP.177.Lu-E5

[0285] ##STR00110##

[0286] Using general synthetic method E, .sup.177Lu-E5 with a radiochemical purity of 96.8% was obtained as shown in Table 8, and the labeling yield was 100%.

TABLE-US-00008 TABLE 8 Region: .sup.177Lu Detector: PMT Start Finish Rate of Area % ROI % Total Name (mm) (mm) flow (RF) (Counts) (%) proportion (%) Region 1 0.2 30.4 0.013 22956 100.00 96.76 1 peak 22956 100.00 96.76 Total area: 23725 Counts Average background: 0 Counts

Example 34: Synthesis of Metal Complex .SUP.177.Lu-PSMA-617

[0287] ##STR00111##

[0288] Using general synthetic method E, .sup.177Lu-PSMA-617 with a radiochemical purity of 98.9% was obtained as shown in Table 9, and the labeling yield was 100%.

TABLE-US-00009 TABLE 9 Region: .sup.177Lu Detector: PMT Start Finish Rate of Area % ROI % Total Name (mm) (mm) flow (RF) (Counts) (%) proportion (%) Region 1 0.0 30.8 0.003 12598 99.14 98.00 Region 2 82.0 94.0 0.970 110 0.86 0.85 2 peaks 12708 100.00 98.85 Total area: 12855 Counts Average background: 0 Counts

Example 35: Labeling Test of Compound .SUP.68.Ga

[0289] The selected E series compounds were dissolved in DMSO to make a 1 mg/mL solution, and a portion was taken out and diluted with PBS to a 0.1 mg/mL solution for later use. A germanium-gallium generator was rinsed with 5 mL of 0.1 M HCl in stages. The part with the highest activity (0.5 mL) was taken, and 0.5 mL of metal-free sodium acetate buffer (pH=4.5) was added. A 1.5 mL centrifuge tube was used as the reactor, and a certain amount of the precursor (0.1 mg/mL) was added, vortexed to mix for 10 s, heated at 95 C. and 800 rpm for 15 min, and then cooled to room temperature. The reaction solution was passed through a C18 column activated with absolute ethanol and water, and the labeled components were collected for later use. The radiochemical purity of the labeled compound was determined by TLC method.

Effect Example 1: Assay of the Uptake of Labeled Compounds by PSMA-Positive Cells LNCap

[0290] LNCap cells (Shangcheng Beina Chuanglian Biotechnology Co., Ltd., Industrial Park, Chengguan Town, Shangcheng County, Xinyang City, Henan Province) were revived and passaged for expansion. After the cells were expanded to a sufficient amount, cells were seeded in a 24-well plate at a density of 110.sup.4 cells/well. Uptake tests were performed when cells grew to 80%-90% confluence.

[0291] The above labeled compounds .sup.177Lu-E1, .sup.177Lu-E2, .sup.177Lu-E3, .sup.177Lu-E5, .sup.177Lu-E9, .sup.177Lu-E14 and .sup.177Lu-PSMA-617 were diluted with serum-free medium into 10000, 1000, 100, 10, 1, 0.1 and 0 nM. 1 mL of the diluted solution was added to a 24-well plate, and incubated at 37 C. for 0.5 h. The supernatant was discarded and the cells were washed 3 times with PBS. 250 L of 1M NaOH solution was added to each well. The cells were pipetted until they were completely dissolved, and transferred to a scintillation vial. 250 L of NaOH solution was added to each well again to wash the bottom of the well and transferred to a scintillation vial. 2 mL of scintillation fluid was added to each scintillation vial and shaken well. A liquid scintillation counter was used to detect radioactive counts in each vial. The uptake of different concentrations of precursor compounds by LNCap cells is shown in the table below:

TABLE-US-00010 0 nM 0.1 nM 1 nM 10 nM 100 nM 1000 nM 10000 nM (cpm) (cpm) (cpm) (cpm) (cpm) (cpm) (cpm) .sup.177Lu-E1 47 39 169 77 121 331 1595 .sup.177Lu-E2 47 29 91 344 596 775 1328 .sup.177Lu-E3 47 48 95 346 555 903 3150 .sup.177Lu-E5 47 52 70 271 420 520 880 .sup.177Lu-E9 47 56 55 84 140 405 1194 .sup.177Lu-E14 47 28 82 220 345 479 362 .sup.177LuPSMA-617 47 49 67 225 389 599 1625

Effect Example 2: In Vivo Metabolism Test of .SUP.177.Lu-Labeled Complex in SD Rats

[0292] Eighteen SD rats (Hangzhou Ziyuan Experimental Animal Technology Co., Ltd.), male, weighing 180-200 g, were randomly divided into 6 groups, 3 rats in each group. 10 Ci of the labeled precursor compound was injected into the tail vein of each mouse. 250 L of orbital blood was collected into anticoagulant tubes at 5 min, 0.5 h, 1 h, 2 h, 4 h, 8 h and 24 h after administration. Blood was centrifuged at 3000 rpm for 10 min, and 100 L of plasma was taken into scintillation vials. 2 mL of scintillation fluid was added to each scintillation vial and shaken well. A liquid scintillation counter was used to detect radioactive counts in each vial.

[0293] The metabolism of the labeled compound in SD rats is shown in the table below:

TABLE-US-00011 Rat 0.083333333 h 0.5 h 1 h 2 h 4 h 8 h 24 h Compound ID (cpm) (cpm) (cpm) (cpm) (cpm) (cpm) (cpm) .sup.177Lu-E1 1 28305 9829 3505 615 163 174 151 2 17143 8252 3389 1288 315 179 169 3 MEAN 22724 9041 3447 952 239 177 160 .sup.177Lu-E2 4 37703 18427 7473 1863 296 178 167 5 41406 15030 5428 1189 219 190 170 6 MEAN 39555 16729 6451 1526 258 184 169 .sup.177Lu-E3 13 26791 10681 3448 539 178 154 191 14 31372 8675 3676 559 135 191 175 15 27797 8026 2916 458 181 184 179 MEAN 28653 9127 3347 519 165 176 182 .sup.177Lu-E9 19 30764 10391 4483 892 210 171 164 20 38134 12249 4139 652 196 184 162 21 30001 8575 2519 346 197 161 183 MEAN 32966 10405 3714 630 201 172 170 .sup.177Lu-E14 7 42150 18047 7200 1415 203 201 196 8 41058 18268 6304 1686 198 206 175 9 45756 18614 6154 1863 259 203 159 MEAN 42988 18310 6553 1655 220 203 177 .sup.177Lu-PSMA-617 10 24449 9783 3865 679 207 188 173 11 23276 13738 6988 1346 219 187 176 12 22010 14589 7736 1544 225 170 178 MEAN 23245 12703 6196 1190 217 182 176

Effect Example 3: SPECT Imaging

[0294] 100 Ci of .sup.177Lu-labeled .sup.177Lu-E3 and .sup.177Lu-PSMA-617 were injected into mice carrying LNCaP PSMA-positive tumors (Jiangsu Huajing Molecular Imaging and Drug Research Institute Co., Ltd.) through the tail vein respectively. Mice were anesthetized with 2% isoflurane/98% oxygen for SPECT image contrast study. The results are shown in Table 10 and Table 11. It can be seen from Table 10 and Table 11 that compared with .sup.177Lu-PSMA-617, .sup.177Lu-E3 can be rapidly distributed to various organs after entering the animal body; the metabolism of .sup.177Lu-E3 is mainly excreted through the kidney; and the accumulation of .sup.177Lu-E3 in PSMA-positive tumors is significantly higher than that of reference animals injected with .sup.177Lu-PSMA-617.

TABLE-US-00012 TABLE 10 1 h 4 h 8 h 1 d 3 d Averaged Averaged Averaged Averaged Averaged .sup.177Lu-E3 (% ID/cc) (% ID/cc) (% ID/cc) (% ID/cc) (% ID/cc) Tumor 23.56 28.79 31.79 34.01 32.84 Heart 6.44 2.41 1.39 3.23 2.03 Liver 3.08 2.03 2.54 1.94 1.80 Kidney 165.36 129.55 87.74 8.03 3.74 Lung 5.52 3.26 1.82 2.71 2.68

TABLE-US-00013 TABLE 11 .sup.177Lu- 1 h 4 h 8 h 1 d 3 d PSMA- Averaged Averaged Averaged Averaged Averaged 617 (% ID/cc) (% ID/cc) (% ID/cc) (% ID/cc) (% ID/cc) Tumor 19.42 10.68 9.4 2.19 4.76 Heart 1.59 1.47 0.53 1.45 0.46 Liver 1.61 1.27 1.04 1.43 0.96 Kidney 58.17 8.37 4.35 1.16 1.55 Lung 3.30 1.54 0.86 0.85 3.74

Effect Example 4: In Vitro Binding Test of Compound and PSMA Protein

[0295] A Biacore 8K (Cytiva) instrument was used to determine the binding affinity of disclosed compounds to the PSMA protein (Sinobiological). The PSMA protein was captured on SA chips. Before immobilizing the disclosed compounds (flow path 1 and 2, flow rate 10 L/min), the PSMA protein was immobilized on flow path 2 by using flow buffer (10 g/ml, flow rate 5 L/min, injection time 600 s), and 1M NaCl was injected three times consecutively into 50 mM NaOH to condition the sensor surface. After each disclosed compounds injection, isopropanol in 1M NaCl and 50 mM NaOH was used for additional washing (flow path 1, 2, flow rate 10 L/min, injection time 60 s).

[0296] All compounds were dissolved in 100% DMSO and diluted to 10 mM, and then diluted in test buffer (PBS, pH 7.4, 1 mM TCEP (tris-(2-hydroxyethyl)phosphine), 0.05% P20, 2% dimethyl sulfoxide) at an appropriate highest concentration. Analytes were run using the following conditions: 15 C. analysis temperature, analysis steps=all set to LMW kinetics; cycle type=single cycle (90 s contact time, 1800 s separation time, 30 ul/min flow rate, channels 1, 2); channel detection=2-1). Data were evaluated using Biacore Insight evaluation software, and data were fit to a 1:1 binding model.

[0297] Biacore results are shown in Table 12: pK.sub.D=Log K.sub.D, where K.sub.D is the binding affinity of the compounds to PSMA protein measured by Biacore. K.sub.D is expressed by K.sub.D (M)=K.sub.d (1/s)/K.sub.a (1/Ms).

TABLE-US-00014 TABLE 12 Binding affinity of the disclosed compounds to PSMA protein Compound pk.sub.D E1 E2 9.64 E3 9.26 E4 9.57 E5 E6 E7 E8 9.49 E9 9.55 E10 E11 E12 E13 12.46 E14 E15 E16 E17 E18 12.28 E19 E20 12.46 E21 9.82 E22 10.00 E23 E24 15.53 E25 10.15 E26 9.44 PSMA-617 11.69

[0298] The results of the above tests show that the PSMA inhibitors obtained with fused aromatic rings, bridged carbocyclic rings, and secondary amine compounds as linkers not only have a good biological activity against PSMA proteins, but also several compounds show better in vitro biological activity comparing to the reference PSMA-617.

Effect Example 5: Determination of the Ability of Cell Binding and Cell Endocytosis

[0299] LNCAP cells in the logarithmic growth phase (Obio Technology (Shanghai) Corp., Ltd.) were made into a cell suspension. The cell suspension was adjusted to a cell density of 210.sup.5/ml and inoculated 1 mL into a 24-well cell culture plate. Cells were incubated in an incubator at 37 C. for 48 hours. Three hours before the test, the medium was replaced with serum-free RPMI1640 medium (NEWZERUM), the cell culture medium was aspirated, and the cells were washed once with PBS. Serum-free RPMI1640 medium was used to prepare .sup.177Lu-E series compounds at concentrations of 32, 16, 8, 4, 1, 0.5, 0.1, 0.02, 0.01, 0.002 uCi/mL. The original medium was discarded, and then 1 mL of the prepared solution containing .sup.177Lu-E series compounds was added to each well. The plate was placed on ice for 2 hours, and then the cells were washed three times with 0.5 mL of ice-cold PBS. The washing solution was aspirated, and the cells were lysed with 0.5 mL of 1M NaOH and washed twice with 0.5 mL of PBS, and the sodium hydroxide (0.5 mL) and PBS (0.5 mL2) solutions were collected. The uptake counts were determined.

[0300] The results of the cell binding tests are shown in FIG. 1. It can be seen from FIG. 1 that the cell binding test shows that the tested compounds have a good ability to bind to PSMA cells, especially compound E26 has an excellent cell binding ability.

[0301] Endocytosis tests: LNCAP cells in logarithmic growth phase (Mall Beina Chuanglian Biotechnology Co., Ltd.) were made into a cell suspension. The cell suspension was adjusted to a cell density of 110.sup.5/m1 and seeded 1 mL into a 12-well cell culture plate. Cells were incubated in an incubator at 37 C. for 48 hours. The medium was replaced with serum-free RPMI1640 medium 3 hours before the test. The cell culture medium was aspirated, and the cells were washed once with PBS.

[0302] Both the E series compounds and the reference compound PSMA-617 were labeled with .sup.177Lu and formulated with physiological saline (containing 0.05% of BSA) to a solution of 47.36 MBq (1280 uci)/mL. The above solution was diluted with serum-free medium, and added into the plate, so that the concentration of the labeled compound in each well was (5 uci/well); The cells were incubated in an incubator at 37 C. for 2 hours, and then washed three times with ice-cold PBS. The washing solution was aspirated, and 0.5M glycine buffer (100 mM NaCl, pH2,8, adjusted with hydrochloric acid) was added. The cells were incubated for 10 minutes and washed three times with 0.5M glycine buffer. The washing solution was aspirated, and collected. The cells were lysed with 0.5 mL of 1M sodium hydroxide, and washed twice with 0.5 mL of PBS. The sodium hydroxide (0.5 mL) and PBS (0.5 mL2) solutions were collected, and the uptake counts were determined.

[0303] FIG. 2 shows the results of the endocytosis test. Combined with the results of the above examples, the E series compounds not only have higher cell affinity, but also show the property of being more easily endocytosed by cells than the reference compound PSMA-617 in the endocytosis test at 37 C. Endocytosis is of great significance for the absorption and retention of radiolabeled compounds in tumor cells, because it directly affects the application of compounds containing radioactive substances in tumor treatment.

Effect Example 6: Specificity Test of E Series Compounds

[0304] The .sup.68Ga-E3 radiolabeled compound was injected into the tail vein of PSMA-positive (22RV1) tumor-bearing mice (Jiangsu Huajing Molecular Imaging and Drug Research Institute Co., Ltd.) (about 7.4 MBq/mouse, specific activity: 22423.82 KBq/g) (50 uCi). After administration, PET/CT was used for 1 h dynamic scanning, medium resolution whole body CT, and 10 min static scanning at 2 h and 3 h. It can be clearly seen from FIG. 3 that the drug is rapidly distributed into the animal body after administration, and the drug is rapidly metabolized by the kidneys and excreted from the body over time. The enrichment of the drug on PSMA expressing tumors reaches the highest level at about 30 minutes after administration, and then it is gradually washed out of the body, but there is still a relatively high .sup.68Ga-E3 enrichment on the tumor at 180 minutes.

[0305] The next day, the mixture of .sup.68Ga-E3 and PSMA standard PMPA (2 mg/Kg) was injected into the tail vein of PSMA-positive tumor-bearing mice (about 7.4 MBq/mouse, specific activity: 22423.82 KBq/g) (50 uCi). After administration, PET/CT was used for 1 h dynamic scanning, medium resolution whole body CT, and 10 min static scanning at 2 h and 3 h. The results are depicted in detailed in FIG. 4.

[0306] PMPA is a specific inhibitor of PSMA. When PMPA is administered together with .sup.68Ga-E3, .sup.68Ga-E3 and PMPA are rapidly distributed to various organs in the animal body. However, PMPA occupies the PSMA target on the tumor, thus preventing the binding of .sup.68Ga-E3 to PSMA on the tumor. This result reflects that E3 has high specificity against PSMA.

Effect Example 7: Determination of cLog P

[0307] Three EP tubes were taken, and 0.5 mL of saturated n-octanol and 480 L of ultrapure water were added into each EP tube. 20 L (about 1 MBq) solution of E series compounds and reference compound were then added respectively. The mixture was shaken evenly and then centrifuged at room temperature (2000 r/min, 5 min, centrifugal radius: 10 cm). 100 L was taken from the lipid layer and aqueous layer of each tube, and the radioactive counts per minute of the two phases were measured. The Log P value was calculated and the results were averaged.

[0308] The Log P test results shown in FIG. 5 show that the tested E series compounds all have good hydrophilicity, among which E3 and E22 have similar lipophilicity compared with the reference compound PSMA-617, while E26 has better lipophilicity. In addition, the value of ClogP shows that the tested compounds all have good water solubility.

Effect Example 8: Determination of Plasma Protein Binding (PPB) Binding of E Series Compounds

[0309] Three EP tubes were taken, and 0.2 mL of plasma and 50 L of .sup.177Lu-labeled compound were added to each tube. The mixture was incubated in a thermostat at 37 C. for 10 min, and then taken out and added to ultrafiltration tubes, respectively. The ultrafiltration tubes were centrifuged at 13,000 rpm for 45 min. 50 L of normal saline was then added, and the mixture was centrifuged for another 15 minutes. The radioactive counts per minute of each tube casing and filtrate were then measured. PPB was calculated, and the mean of 3 tubes was recorded. PPB=[(supernatant counts-background counts)]/(subnatant counts+supernatant counts2*background counts)]*100.

[0310] The degree of binding rate of compound to plasma protein (PPB) plays an important role in the circulation of the compound in the blood. Although E3 has similar lipophilicity to the reference compound PSMA-617 either from the structure of the compound or from the Log P results of the compound (FIG. 6), E3 exhibits an extremely high PPB binding rate, which is of great significance for the retention of the compound in the blood.

Effect Example 9: Bio-Distribution of E Series Compounds

[0311] In vivo distribution in healthy rats: Radiolabeled E series compounds were injected into the tail vein of SD rats aged 6-9 weeks (Hangzhou Ziyuan Testal Animal Technology Co., Ltd.) (about 7.4 MBq/mouse, specific activity: 84200.14 kBq/g). At different time points (0.25, 0.5, 1, 2, 4, 6, 24, 48, 72 h) after administration of labeled compounds to SD rats, the animals were euthanized by carbon dioxide inhalation, and the blood and 16 viscera (blood, liver, spleen, lungs, heart, muscle, pancreas, testes) of the animals were collected after euthanasia.

[0312] Blood was collected through the abdominal aorta, and immediately after collection, 100 L was quantified into a designated centrifuge tube (weighed). After the viscera were collected, they were washed twice with deionized water, wiped dry, put into a pre-weighed test tube, and weighed again. The weight of samples was calculated. The sample was measured on the day of collection. All blood samples and tissue samples were measured for radioactive counts using a gamma counter.

[0313] The test results shown in FIG. 7 show that after intravenous administration, .sup.177Lu-E3 can be rapidly distributed to various organs of healthy rats and then quickly washed out of the body; the main pathway of drug elimination is accomplished through the kidneys; the uptake of .sup.177Lu-E3 in each organ is low, and shows good pharmacokinetic properties.

[0314] Tissue distribution in PSMA-positive tumor-bearing mice: About 6-9 weeks old (Nod scid) mice (Jiangsu Huajing Molecular Imaging and Drug Research Institute Co., Ltd.) were inoculated subcutaneously with 510.sup.6 cells of 22rv1 (in 50% Matrigel, Corning) on the right shoulder of animals. When the tumor grew to a size of about 150-350 mm.sup.3, .sup.177Lu-E3 radiolabeled compound was injected into the tail vein of the mouse (about 7.4 MBq/mouse, specific activity: 22423.82 KBq/g). The animals were euthanized by carbon dioxide inhalation at 0.25, 0.5, 1, 6, 24, 72, 144, and 168 hours respectively after administration. Blood and viscera (blood, liver, spleen, lung, heart, muscle, pancreas, testis, tumor) were collected from animals after euthanasia.

[0315] Blood was collected through the abdominal aorta, and immediately after collection, 100 L was quantified into a designated centrifuge tube (weighed). After the viscera were collected, they were washed twice with deionized water and wiped dry. The viscera were put into a pre-weighed test tube, and weighed again. The weight of the sample was calculated. The sample was measured on the day of collection. All blood samples and tissue samples were measured for radioactive counts using a gamma counter, and the results are shown in FIG. 8.

[0316] After intravenous administration, .sup.177Lu-E3 is quickly distributed to various organs of tumor-bearing mice. The clearance rate in the blood is relatively fast, and .sup.177Lu-E3 was excreted through renal excretion. The uptake of .sup.177Lu-E3 in the tumor reached the highest level 2 hours after administration, and then decreased over time. But even after 7 days, the tumor still contained a high drug concentration. In addition, the uptake in non-target organs is always low and was quickly washed out of the body.

Effect Example 10

[0317] About 4-5 weeks old (balb/c nude, Beijing Vital River) mice were subcutaneously inoculated with 510.sup.6 cells of 22rv1 (in 50% Matrigel, Corning) on the right scapula of animals. When the tumor grew to a size of about 150-350 mm.sup.3, after anesthesia with isoflurane, .sup.177Lu-PSMA-617, .sup.177Lu-E3, .sup.177Lu-E4, .sup.177Lu-E8, .sup.177Lu-E16, .sup.177Lu-E18, .sup.177Lu-E24 radiolabeled compounds were injected into the tail vein of mice (about 7.4 MBq/mouse, specific activity: 22423.82 KBq/g). Subsequently, SPECT imaging was performed with a small animal SPECT-CT imaging system (U-SPECT+/CT, MI Labs) at 1 h, 5 h, 24 h, 48 h and 72 h, respectively. .sup.177Lu-PSMA-617 is shown in FIG. 9, .sup.177Lu-E3 is shown in FIG. 10, .sup.177Lu-E4 is shown in FIG. 11, .sup.177Lu-E8 is shown in FIG. 12, .sup.177Lu-E16 is shown in FIG. 13, .sup.177Lu-E8 is shown in FIG. 14, and .sup.177Lu-E24 is shown in FIG. 15. The results of imaging tests show that after these .sup.177Lu-labeled E compounds enter the animal body through the tail vein of the animal, they can be quickly distributed to various organs of the animal and then quickly washed out of the body. The main way of drug elimination is through the kidney. The residence time of .sup.177Lu-E8, .sup.177Lu-E16, and .sup.177Lu-E24 in both of animals and tumors expressing PSMA is relatively short, and these compounds are basically washed out of body after 1 hour. Comparing with .sup.177Lu-PSMA-617, .sup.177Lu-E3, .sup.177Lu-E4, and .sup.177Lu-E8 can also be rapidly excreted from animal body, the PSMA-expressing tumors contain higher uptake of radioactivity while the rest organs show radioactivity as the same as that in background. .sup.177Lu-E3 and .sup.177Lu-E18 still show high specific absorption in PSMA-expressing tumors even after 72 hours.

Effect Example 11

[0318] About 4-5 weeks (nod scid, Jiangsu Huajing Molecular Imaging and Drug Research Institute Co., Ltd.) mice were inoculated subcutaneously with 110.sup.6 cells of 22rv1 (in 50% Matrigel, Corning) on the right scapula of animals. When the tumor grew to the size required by the test, the animals were randomly assigned to 5 test groups according to the tumor volume, with 7 animals in each group, and the body weight and tumor size of the animals were measured. On the day of grouping, the control group (normal saline), group 1 (.sup.177Lu-PSMA-617 300 mCi/animal), group 2 (.sup.177Lu-PSMA-617 600 mCi/animal), group 3 (.sup.177Lu-E3 300 mCi/animal), and group 4 (.sup.177Lu-E3 600 mCi/animal) began to be administered. General health and appearance observations were carried out every day after the start of the test, and the body weight and tumor size of animals were measured before each sample sampling time point. Any unusual observations discovered throughout the study period will be recorded in the raw data. The results of animal weight changes were shown in FIG. 16, and the results of tumor size changes are shown in FIG. 17 and Table 13.

TABLE-US-00015 Tumor volume (mm.sup.3).sup.a Administration in Before groups TGI.sub.TV Group Test sample administration Day 19 (%) P.sup.b G1 Control 126.09 29.31 1,727.18 435.06 G2 300 Ci (PSMA-617) 126.96 29.56 1,480.09 446.83 15.49% 0.3547 G3 600 Ci (PSMA-617) 127.86 29.25 1,389.81 598.96 21.18% 0.2904 G4 300 Ci (E3) 126.41 26.77 .sup.590.66 103.97 71.00% <0.0001 G5 600 Ci (E3) 133.60 35.46 447.12 47.84 80.42% <0.0001 Note: .sup.aMean standard error; .sup.bStatistical comparison between the tumor volumes of the administration group and the control group on the 19th day after administration in groups, T-test.

[0319] The relative tumor inhibition rate is represented by TGI.sub.TV(%)=[1-(T.sub.iT.sub.0)/(V.sub.iV.sub.0)]100% (T.sub.i: the mean tumor volume of the treatment group on the i-th day of administration, To: the mean tumor volume of the treatment group on the 0th day of administration; V.sub.i: the mean tumor volume of the vehicle control group on the i-th day of administration, V.sub.0: the mean tumor volume of the vehicle control group on the 0th day of administration.

[0320] The test results show that the efficacy of .sup.177Lu-E3 in the mouse xenograft tumor model is significantly improved. Comparing with 15-21% of the tumor inhibition rate of .sup.177Lu-PSMA-617, the tumor growth inhibition rate of .sup.177Lu-E3 reaches 71-80%. Moreover, the two dosing groups of animals treated with .sup.177Lu-E3 show no significant difference in the inhibitory effect on tumor growth within the first 10 days after medication. Then it gradually shows the dose-related efficacy difference. The analysis of the overall data of .sup.177Lu-E3 in the two dose groups shows statistically significant. The results of this experiment demonstrate that .sup.177Lu-E3 has a better inhibitory effect on the growth of tumors expressing PSMA than .sup.177Lu-PSMA-617 at the same dose. The efficient inhibitory effect can reduce the drug dose when it is used, which not only can reduce the potential radiation-related drug toxicity, also can reduce drug costs.

[0321] Finally, the above-mentioned general description and specific implementation examples have described the present disclosure in detail. Through these descriptions, those skilled in the art can obviously make some modifications or improvements to the present disclosure on the basis of the present disclosure. Therefore, any modification or improvement made without departing from the spirit of the present disclosure belongs to the protection scope of the present disclosure.