40299-19-2

Upstream product

• 13734-41-3 t-Boc-L-valine 
• 619-73-8 4-nitrobenzyl chloride 

Relevant academic research and scientific papers

1-METHYLCARBAPENEM DERIVATIVES

The present invention relates to 1-methylcarbapenem compounds having excellent antibacterial activity, pharmacologically acceptable ester derivatives thereof, pharmacologically acceptable salts thereof, pharmaceutical compositions (particularly antibacterial agents) containing them as active ingredient, use of the compounds, ester derivatives or salts thereof for preparing such pharmaceutical compositions and a method of preventing or treating diseases (particularly bacterial infections) in which a pharmacologically effective amount of the compound, ester derivative or salt is administered to a warm-blooded animal (particularly a human being). The 1-methylcarbapenem compounds of the present invention are represented by the general formula (I): wherein:R1 is a group represented by the formula COOR3 (wherein R3 represents a hydrogen atom, a C1-C6 alkyl group or the like), a group represented by the formula CONR4R5 (wherein R4 and R5 each independently represent a hydrogen atom, a C1-C6 alkyl group which may be substituted or the like), a cyano group, a group represented by the formula CH2OR6 (wherein R6 represents a hydrogen atom, a C1-C6 alkyl group or the like) or a group represented by the formula CH2NR7R8 (wherein R7 represents a hydrogen atom, a C1-C6 alkyl group or the like, and R8 represents a hydrogen atom, a C1-C6 alkyl group, a C1-C6 alkanoyl group, a C1- C6 alkoxycarbonyl group or the like);R2 represents a hydrogen atom or a C1-C6 alkyl group;n represents 1, 2 or 3; andX represents a sulfur atom or an oxygen atom.

ISOPROPENYL CHLOROCARBONATE (IPCC) IN AMINO ACID AND PEPTIDE CHEMISTRY: ESTERIFICATION OF N-PROTECTED AMINO ACIDS; APPLICATION TO THE SYNTHESIS OF THE DEPSIPEPTIDE VALINOMYCIN

Esterification of N-protected α-amino acids was achieved via isopropenyl chlorocarbonate (IPCC) activation.In situ alcoholysis of the unstable mixed anhydride intermediate was catalised by 4-(dimethylamino)pyridine (DMAP).Competing isopropenyl ester formation was negligible when using methylene chloride as the solvent.A variety of esters from primary and secondary alcohols were obtained with good yields (60 to 90 percent), and even the more hindered tertiobutyl alcohol gave acceptable yields under more drastic conditions.The improvement in depsipeptide synthetic methodology is illustrated by preparation of the antibiotic valinomycin, using IPCC for ester bond formation, and BOP reagent for peptide coupling and the last-step cyclisation.

2,2'-CARBONYL-BIS(3,5-DIOXO-4-METHYL-1,2,4-OXADIAZOLIDINE) : II- REAGENT FOR THE DIRECT ESTERIFICATION OF CARBOXYLIC ACIDS.

Reaction of carboxylic acids including N-protected α-amino acids with 2,2'-carbonyl bis(3,5-dioxo-4-methyl-1,2,4-oxadiazolidine) and alcohols affords the corresponding esters under mild conditions.