A new enzymatic method for synthesis of enantiomerically enriched δ-hexadecalactone (3) based on the enzymatic kinetic resolution of N-methyl-5-acetoxyhexadecanamide (1) is described. A combination of lipase-catalyzed hydrolysis and amidation improved enantioselectivity. Lipase-catalyzed amidation was also investigated. Detailed screening of solvents and additive amines was performed. The addit...

The use of B(OCH2CF3)3 for mediating direct amidation reactions of a wide range of pharmaceutically relevant carboxylic acids and amines is described, including numerous heterocycle-containing examples. An initial screen of solvents for the direct amidation reaction suggested that cyclopentyl methyl ether, a solvent with a very good safety profile suitable for use over a wide temperature range,...

The glutamic acid residues of the peptidoglycan of Staphylococcus aureus and many other bacteria become amidated by an as yet unknown mechanism. In this communication we describe the identification, in the genome of S. aureus strain COL, of two co-transcribed genes, murT and gatD, which are responsible for peptidoglycan amidation. MurT and GatD have sequence similarity to substrate-binding doma...

Esters are one of the most common functional groups in natural and synthetic products, and the one-step conversion of the ester group into other functional groups is an attractive strategy in organic synthesis. Direct amidation of esters is particularly appealing due to the omnipresence of the amide moiety in biomolecules, fine chemicals, and drug candidates. However, efficient methods for dire...

BACKGROUND During development of recombinant monoclonal antibodies in Chinese hamster ovary (CHO) cells, C-terminal amidated species are observed. C-terminal amidation is catalysed by peptidylglycine α-amidating monooxygenase (PAM), an enzyme known to be expressed in CHO cells. The significant variations between clones during clone selection, and the relatively high content of amidated species ...

The peptidoglycan (PG) of Lactobacillus plantarum contains amidated meso-diaminopimelic acid (mDAP). The functional role of this PG modification has never been characterized in any bacterial species, except for its impact on PG recognition by receptors of the innate immune system. In silico analysis of loci carrying PG biosynthesis genes in the L. plantarum genome revealed the colocalization of...

Cobyrinic acid a,c-diamide synthetase from Salmonella typhimurium (CbiA) is the first glutamine amidotransferase in the anaerobic biosynthetic pathway of vitamin B(12) and catalyzes the ATP-dependent synthesis of cobyrinic acid a,c-diamide from cobyrinic acid using either glutamine or ammonia as the nitrogen source. The cbiA gene was cloned, the overexpressed protein was purified to homogeneity...

A secretory granule associated enzymatic activity from the rat anterior pituitary that can convert the synthetic peptide D-Tyr-Val-Gly into D-Tyr-Val-NH2 is described. Due to the presence of inhibitory activity in the cytosol and rough endoplasmic reticulum/Golgi apparatus fractions, the a-amidation activity is barely detectable in crude rat anterior pituitary homogenates. The a-amidation activ...

A new, effective preparative method has been proposed and the synthesis of a series of N-(arylalkyl)-1-R-4-hydroxy-2,2-dioxo-1H-2λ(6),1-benzothiazine-3-car-boxamides has been carried out. It has been shown that amidation of alkyl 1-R-4-hydroxy-2,2-dioxo-1H-2λ(6),1-benzothiazine-3-carboxylates with arylalkyl-amines in boiling xylene proceeds with good yield and purity to the corresponding N-(ary...

As potential new analgesics, the corresponding 4-hydroxy-2,2-dioxo-1H-2λ⁶,1-benzothiazine-3-carboxanilides have been obtained by amidation of ethyl 4-hydroxy-2,2-dioxo-1H-2λ⁶,1-benzothiazine-3-carboxylate with aniline and its halogenated analogsin boiling dry xylene. The peculiarities of the mass and nuclear magnetic resonance (¹Н and 13С) spectra of the synthesized compounds are discussed. Usi...