Disclosed in the present invention are an aromatic vinyl or aromatic ethyl derivative, a preparation method therefor, an intermediate, a pharmaceutical composition, and an application. The aromatic vinyl or aromatic ethyl derivative in the present invention is as represented by general formula (I). The aromatic vinyl or aromatic ethyl derivative in the present invention has an obvious inhibitory effect on PD-1/PD-L1, is a very effective small-molecule PD-1/PD-L1 inhibitor, and can effectively alleviate or treat relevant diseases such as cancer.

##STR00001##

Provided is a method of preparing L-homoserine, the method including contacting an L-homoserine derivative with a solid acid catalyst.

Provided is a method of preparing L-homoserine, the method including contacting an L-homoserine derivative with a solid acid catalyst.

Disclosed are compounds having the following formula (I):Formula (I) wherein R is an alkylene chain having between 8 and 20 carbon atoms, and A is one or more anions having a total charge of −2, or R is a quaternary amine having the following formula (Ia):Formula (Ia) wherein R.sub.a and R.sub.b are each an alkylene chain having between 8 and 20 carbon atoms, and A is one or more anions having a total charge of −3; R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5 and R.sub.6 are each independently selected from C.sub.1-10 alkyl and H; E has the following Formula (Ib), wherein the ester oxygen is bonded to the aromatic ring of each E at the same position, the position being position 2 or 3; and wherein R.sub.E is H or a halide.

##STR00001##

Disclosed are compounds having the following formula (I):Formula (I) wherein R is an alkylene chain having between 8 and 20 carbon atoms, and A is one or more anions having a total charge of −2, or R is a quaternary amine having the following formula (Ia):Formula (Ia) wherein R.sub.a and R.sub.b are each an alkylene chain having between 8 and 20 carbon atoms, and A is one or more anions having a total charge of −3; R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5 and R.sub.6 are each independently selected from C.sub.1-10 alkyl and H; E has the following Formula (Ib), wherein the ester oxygen is bonded to the aromatic ring of each E at the same position, the position being position 2 or 3; and wherein R.sub.E is H or a halide.

##STR00001##

Disclosed in the present invention are an aromatic vinyl or aromatic ethyl derivative, a preparation method therefor, an intermediate, a pharmaceutical composition, and an application. The aromatic vinyl or aromatic ethyl derivative in the present invention is as represented by general formula (I). The aromatic vinyl or aromatic ethyl derivative in the present invention has an obvious inhibitory effect on PD-1/PD-L1, is a very effective small-molecule PD-1/PD-L1 inhibitor, and can effectively alleviate or treat relevant diseases such as cancer. ##STR00001##

Disclosed in the present invention are an aromatic vinyl or aromatic ethyl derivative, a preparation method therefor, an intermediate, a pharmaceutical composition, and an application. The aromatic vinyl or aromatic ethyl derivative in the present invention is as represented by general formula (I). The aromatic vinyl or aromatic ethyl derivative in the present invention has an obvious inhibitory effect on PD-1/PD-L1, is a very effective small-molecule PD-1/PD-L1 inhibitor, and can effectively alleviate or treat relevant diseases such as cancer. ##STR00001##

A chemical synthesis platform based on a particularly simple chip is described herein, where reactions take place atop a hydrophobic substrate patterned with a circular hydrophilic liquid trap. The overall supporting hardware (heater, rotating carousel of reagent dispensers, etc.) can be packaged into a very compact format (about the size of a coffee cup). We demonstrate the consistent synthesis of [.sup.18F]fallypride with high yield, and show that protocols optimized using a high-throughput optimization platform we have developed can be readily translated to this device with no changes or reoptimization.

A chemical synthesis platform based on a particularly simple chip is described herein, where reactions take place atop a hydrophobic substrate patterned with a circular hydrophilic liquid trap. The overall supporting hardware (heater, rotating carousel of reagent dispensers, etc.) can be packaged into a very compact format (about the size of a coffee cup). We demonstrate the consistent synthesis of [.sup.18F]fallypride with high yield, and show that protocols optimized using a high-throughput optimization platform we have developed can be readily translated to this device with no changes or reoptimization.

The present disclosure is directed synthetic methods for the preparation of 4-valyloxybutyric acid. The synthetic methods described herein employ a diverse array of protecting group strategies and reaction conditions. Additionally, the present disclosure is directed to compounds useful as synthetic intermediates in the preparation of 4-valyloxybutyric acid.