Provided are compounds and salts having a structure of Formula (I) or (II): (I), and (II) wherein: both of the chiral carbon atoms denoted by “*” are both in the R configuration or both in the S configuration. Compounds and salts of Formulae (I) and (II) are useful in the preparation of enantiomerically pure amino acids. Conversion of amino acids to D-form from any of L-form, racemate or other enantiomerically impure mixtures or conversion of amino acids to L-form from any of D-form, racemate or other enantiomerically impure mixtures is disclosed.

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Disclosed are an etelcalcetide intermediate and a method for synthesizing etelcalcetide. The etelcalcetide intermediate is Fmoc-D-Cys(S—S—(N-Boc)-L-Cys(OtBu))-OH. The method for synthesizing the etelcalcetide includes the following steps: using N-Boc-L-Cqs-OtBu as a starting material to generate a primary product of a formula (A) by means of a substitution reaction, herein R is S-Py or Cl; and performing a coupling reaction on the primary product and Fmoc-D-Cys-OH amino acid to obtain Fmoc-D-Cys(S—S—(N-Boc)-L-Cys(OtBu))-OH. The key intermediate is used for synthesizing the etelcalcetide, which may improve the purity and the yield. It is important that the raw materials for synthesizing the key intermediate are cheap and readily available, and the process is simple.

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A fucosylated chondroitin sulfate oligosaccharide having the structure as shown in J, and further disclosed is a method for preparing the fucosylated chondroitin sulfate oligosaccharide: using a chondroitin sulfate A salt as a raw material, sequentially performing enzymolysis, a group protection operation, and glycosylation to synthesize the oligosaccharide compound; the certainty of the described structure allows said oligosaccharide to be applied to the medical field.

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A process for manufacturing substituted chroman compounds in an economically scalable manner, without the use of pyrophoric reagents. Also disclosed herein are chroman compound synthesis routes that do not include column chromatography purification steps. The disclosure also relates to the intermediates used in the synthesis. In particular, the disclosure relates to the synthesis of the Calcium sensing receptor (CaSR) modulating agent 2-methyl-5-((2R,4S)-2-((((R)-1-(naphthalen-1-yl)ethyl)amino)methyl)chroman-4-yl)benzoic acid, its intermediates and pharmaceutically acceptable salts thereof.

The present invention belongs to the field of medicinal chemistry. Disclosed are a pyridine oxynitride, a preparation method therefor and the use thereof. Specifically, the present invention relates to a series of sodium ion channel blockers with a new structure, a preparation method therefor and the use thereof. The structure thereof is as shown in general formula (I) below. The compounds or a stereoisomer, a racemate, a geometric isomer, a tautomer, a prodrug, a hydrate, a solvate, or a pharmaceutically acceptable salt thereof and a pharmaceutical composition can be used for treating or/and preventing related diseases mediated by a sodium ion channel (NaV).

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An EP300/CBP inhibitor, specifically provided is a compound as shown in formula I, or a deuterated product thereof, or a salt thereof, or a conformational isomer thereof, or a crystal form thereof, or a solvate thereof. The compound is highly selective for EP300/CBP, and can effectively inhibit the activity of EP300/CBP; in addition, the compound has an excellent inhibitory effect on various tumor cells including prostate cancer cells, leukemia cells, breast cancer cells and multiple myeloma cells. The compound has broad application prospects in the preparation of an EP300/CBP inhibitor, and drugs for preventing and/or treating tumors, myeloid hematopoietic stem/progenitor cells malignant disease, and regulating regulatory T cells.

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A purpose of the present invention is to provide a method for producing a glycoside compound having a high purity. The present invention provides a method for producing a glycoside compound represented by formula (3) (wherein B.sup.a, i-Pr and n are the same as those defined below), which comprises reacting a glycoside compound of formula (1) (wherein B.sup.a represents an adenine group which may be optionally substituted with an acyl group, and i-Pr represents an isopropyl group) with an ether compound of formula (2) (wherein R.sup.1 represents a C1-C6 alkyl group or a phenyl group, and n is 0 or 1) in one or more solvents selected from tetrahydropyran and 4-methyltetrahydropyran in the presence of one or more halogenated agents selected from halogen, N-halogenated succinimide, and N-halogenated hydantoin.

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The present invention provides an amidite compound capable of improving a yield and a purity of a polyoligonucleotide, a glycoside compound as an intermediate thereof, and a production method for a polynucleotide using the amidite compound. The present invention also provides an amidite compound of formula (1) capable of improving a yield and a purity of a polyoligonucleotide, a glycoside compound of formula (10) (in formulae (10) and (1), B.sup.a, R.sup.a, R.sup.b, R.sup.c, G.sup.1, G.sup.2, and G.sup.3 are as defined in the description, and R is represented by the following formulae), and a production method for a polynucleotide using the amidite compound.

A sulfhydryl modified hyaluronic acid has a high mercaptan content, and a small change in the molecular mass of the main chain molecule, and has a significantly improved viscosity, water retention, and oxidation resistance. It is prepared from hyaluronic acid modified by acryl-based compounds and polysulfhydryl compounds by means of the Michael addition reaction of mercaptan and conjugated double bonds. The preparation method can flexibly control the structure and composition of a synthesized product, the type and content of the terminal functional group of a large number of compound molecules, etc. The use of a reagent having high biocompatibility effectively controls the production cost and reduces the toxicity during the synthesis.

This invention relates to the use of base-labile protecting groups for stepwise synthesis of polymers including oligomers. One or more monomers that have a base-labile protecting group at one end and a leaving group at the other are used in synthetic cycles comprising deprotection under stronger basic conditions to remove the base-labile protecting group, and coupling with a monomer under weaker basic conditions to elongate the polymer without premature deprotection of the base-labile protecting group. Advantages of the invention include the possibility to shorten the synthetic cycle from three steps in prior art methods to two steps, more efficient deprotection, more efficient coupling, and the use of less harmful and less expensive chemicals. One of the goals for stepwise polymer synthesis is to prepare monodisperse and sequence-defined polymers.