A highly efficient and facile protocol for the selective reduction of carboxylic acid of Fenofibric acid to corresponding alcohol was developed. The selective reduction was carried out by activation of carboxylic acid...A highly efficient and facile protocol for the selective reduction of carboxylic acid of Fenofibric acid to corresponding alcohol was developed. The selective reduction was carried out by activation of carboxylic acid by mixed anhydride followed by the reaction of sodium borohydride in presence of methanol. This is the first example of chemoselective reduction of carboxylic acid to alcohol in presence of a ketone without any external catalyst or ligand in a single step. The reaction offers wide applicability for the selective carboxylic group reduction methodology. The chemoselective reduction was demonstrated by the reduction of Fenofibric acid, an active metabolite of the drug Fenofibrate, to corresponding alcohol in excellent selectivity, yield, and purity.展开更多
N-phosphoryl-α-amino acids can react to form esters, peptides, phosphoryl ester-exchanged products and phosphoryl group migration products under mild conditions, which are very important in researches on arohebiont. ...N-phosphoryl-α-amino acids can react to form esters, peptides, phosphoryl ester-exchanged products and phosphoryl group migration products under mild conditions, which are very important in researches on arohebiont. It has been proposed that intramolecular mixed carboxylic-phosphoric anhydrides (IMCPAs) might be the common intermediates of the reactions, which are difficult to be experimentally observed because of their high activity. In this note, it has been revealed, by means of MNDO, that the IMCPAs are situated at the relatively minimal points of the potential surface and can form in a non-synchronous concerted reaction pathway that passes through a transition state with a hydrogen-bond-bridge structure. The results give a successful explanation to the structure and formation of IMCPAs and their ability to promote the various reactions mentioned above.展开更多
An efficient way to coupling amine with the derivatives of steric N-Boc-pyrrolidine-2-carboxylic acid was reported in this paper. We have found that the synthesis of derivatives is problematic with the commonly used D...An efficient way to coupling amine with the derivatives of steric N-Boc-pyrrolidine-2-carboxylic acid was reported in this paper. We have found that the synthesis of derivatives is problematic with the commonly used DCC/HOBT method. As a substitute, the mixed anhydride method was adopted. A series of 6-（3-nitroguanidino）hexanamidopyrrolidine derivatives were prepared with this method.展开更多
文摘A highly efficient and facile protocol for the selective reduction of carboxylic acid of Fenofibric acid to corresponding alcohol was developed. The selective reduction was carried out by activation of carboxylic acid by mixed anhydride followed by the reaction of sodium borohydride in presence of methanol. This is the first example of chemoselective reduction of carboxylic acid to alcohol in presence of a ketone without any external catalyst or ligand in a single step. The reaction offers wide applicability for the selective carboxylic group reduction methodology. The chemoselective reduction was demonstrated by the reduction of Fenofibric acid, an active metabolite of the drug Fenofibrate, to corresponding alcohol in excellent selectivity, yield, and purity.
文摘N-phosphoryl-α-amino acids can react to form esters, peptides, phosphoryl ester-exchanged products and phosphoryl group migration products under mild conditions, which are very important in researches on arohebiont. It has been proposed that intramolecular mixed carboxylic-phosphoric anhydrides (IMCPAs) might be the common intermediates of the reactions, which are difficult to be experimentally observed because of their high activity. In this note, it has been revealed, by means of MNDO, that the IMCPAs are situated at the relatively minimal points of the potential surface and can form in a non-synchronous concerted reaction pathway that passes through a transition state with a hydrogen-bond-bridge structure. The results give a successful explanation to the structure and formation of IMCPAs and their ability to promote the various reactions mentioned above.
基金the National Natural Science Foundation of China （No. 20272033） for financial support for this work.
文摘An efficient way to coupling amine with the derivatives of steric N-Boc-pyrrolidine-2-carboxylic acid was reported in this paper. We have found that the synthesis of derivatives is problematic with the commonly used DCC/HOBT method. As a substitute, the mixed anhydride method was adopted. A series of 6-（3-nitroguanidino）hexanamidopyrrolidine derivatives were prepared with this method.
