Vacuum ultraviolet laser photodissociation (UVPD) of peptide ions leads to unusual dissociation channels involving backbone C-C bond breaking. However, the molecular basis for the observed behavior is not clearly understood. We now report theoretical investigations using ab initio/density functional theory (DFT) techniques on neutral and protonated dipeptides undergoing vacuum ultraviolet (VUV)...

This paper describes an efficient synthesis and the antiparasitic evaluation of cyclic beta-amino acid-containing dipeptides 3.1-3.6 and 4.1-4.5. The antimalarial properties of all these dipeptides have been evaluated in vitro against Plasmodium falciparum and in vivo against Plasmodium berghai. Compounds 4.4 and 4.5 have been found to be very effective in this respect, with IC50 values of 3.87...

The latency of nitrocatechol sulphatase activity was measured in rat liver lysosomes before and after preincubation in 0.25m solutions of five amino acids, three dipeptides and a tripeptide. Rates of increase in ;free' activity were taken as an indication of rates of solute penetration into lysosomes and were correlated with the structure of each molecule studied. In general permeability was gr...

Density functional theory methods(DFT) and natural bond orbital (NBO) analysis were used to investigate the effects of isomerism and side chain mutation at a microscopic level on the stability, binding energy and NMR/NQR tensors of structural isomers, L- methionylasparagine (Met-Asn) and L- asparagylmethionine (Asn-Met) in the gas phase. The results represented that the isomerism and side chain...

Arginyl dipeptides like Arg-Ser, Arg-Ala, and Arg-Gly are salt-taste enhancers can potentially be used to reduce the salt content of food. The l-amino acid ligase RizA from B. subtilis selectively synthesizes arginyl dipeptides. However, industrial application is prevented by high cost cofactor adenosine triphosphate (ATP). Thus, a coupled reaction system was created consisting acetate kinase (...

A relay catalysis protocol for the functionalization of α-amino acids and dipeptides using a combination of visible-light photoredox and Lewis acid catalysis has been developed.