A successful chiral separation of N-benzoyl phenylalanine methyl ester has been achieved by nonaqueous capillary electrophoresis (NACE) using P-CD as chiral selector in formamide (FA). Some experimental parameters inf...A successful chiral separation of N-benzoyl phenylalanine methyl ester has been achieved by nonaqueous capillary electrophoresis (NACE) using P-CD as chiral selector in formamide (FA). Some experimental parameters influencing the chiral separation such as concentration of P-CD, ionic strength and apparent pH (pH*) are discussed.展开更多
The esterifications of 9-（hydroxyimino）-4-methyl-8,9-dihydrofuro[2,3-h]chromen-2-one （4） with acid chlorides afforded normal oxime-esters 3a-e in 35-78% yields in presence of excessive 4-dimethylaminopyridine as t...The esterifications of 9-（hydroxyimino）-4-methyl-8,9-dihydrofuro[2,3-h]chromen-2-one （4） with acid chlorides afforded normal oxime-esters 3a-e in 35-78% yields in presence of excessive 4-dimethylaminopyridine as the acid scavenger, whereas the reactions gave unexpected 8-substituted products N-（8-chloro-4-methyl-2-oxo-2H-furo-[2,3-h]chromen-9-yl）amides （5a-c） and 4-methyl-2,9-dioxo-8,9-dihydro-2H-furo[2,3-h]chromen-8-ylcarboxyloates （6d-e） by using excessive acid chlorides. The structures of 10 new compounds were determined by 1H NMR, 13C NMR, MS and HRMS, and the possible mechanism for the formation of unexpected products 5a--c and 6d-e was also proposed.展开更多
Threo N benzoyl 3 phenylisoserine methyl ester was synthesized. Compound 3 was first prepared from benzaldehyde and ethyl chloroacetate by Darzens condensation, then through ammonolysis, hydrolysis, acylation and meth...Threo N benzoyl 3 phenylisoserine methyl ester was synthesized. Compound 3 was first prepared from benzaldehyde and ethyl chloroacetate by Darzens condensation, then through ammonolysis, hydrolysis, acylation and methylation, erythro N benzoyl 3 phenylisoserine methyl ester was obtained. The C 2 configuration inversion of the latter compound affords the title compound in yield of 42%. The compound was characterized by IR, 1H NMR and elemental analysis.展开更多
文摘A successful chiral separation of N-benzoyl phenylalanine methyl ester has been achieved by nonaqueous capillary electrophoresis (NACE) using P-CD as chiral selector in formamide (FA). Some experimental parameters influencing the chiral separation such as concentration of P-CD, ionic strength and apparent pH (pH*) are discussed.
基金grants from the National Natural Science Foundation of China (No.20272010 and 20672022)
文摘The esterifications of 9-（hydroxyimino）-4-methyl-8,9-dihydrofuro[2,3-h]chromen-2-one （4） with acid chlorides afforded normal oxime-esters 3a-e in 35-78% yields in presence of excessive 4-dimethylaminopyridine as the acid scavenger, whereas the reactions gave unexpected 8-substituted products N-（8-chloro-4-methyl-2-oxo-2H-furo-[2,3-h]chromen-9-yl）amides （5a-c） and 4-methyl-2,9-dioxo-8,9-dihydro-2H-furo[2,3-h]chromen-8-ylcarboxyloates （6d-e） by using excessive acid chlorides. The structures of 10 new compounds were determined by 1H NMR, 13C NMR, MS and HRMS, and the possible mechanism for the formation of unexpected products 5a--c and 6d-e was also proposed.
文摘Threo N benzoyl 3 phenylisoserine methyl ester was synthesized. Compound 3 was first prepared from benzaldehyde and ethyl chloroacetate by Darzens condensation, then through ammonolysis, hydrolysis, acylation and methylation, erythro N benzoyl 3 phenylisoserine methyl ester was obtained. The C 2 configuration inversion of the latter compound affords the title compound in yield of 42%. The compound was characterized by IR, 1H NMR and elemental analysis.
