Protonated cyclic dipeptides undergo collision-induced dissociation, and this reaction mechanism strongly depends on the symmetry nature of residues. We review main dissociation for a series dipeptides, obtained through chemical dynamics simulations. The systems range from symmetrical cyclo-(glycyl-glycyl), with two possible protonation sites located peptide ring, to cyclo-(tyrosyl-prolyl), whe...

Bacillus amyloliquefaciens Q-426 with strong antifungal activity was isolated from the compost samples in Dalian of China. Four kinds diketopiperazines were extracted strain including cyclo(Pro-Phe) (cPP), which had cyclo(L-Pro-L-Phe), cyclo(D-Phe-L-Pro), cyclo(D-Pro-D-Phe) and cyclo(L-Pro-D-Phe) isomers. Results showed that (1) cPP production reached maximum at 12 h then maintained constant yi...

A synthesis of C17α-OH-tigogenin, the aglycon of aspafiliosides E and F, is described. The main features of the synthesis are three cascade processes, which involve the iodo-lactonization of furostan-26-acid to open ring E, a cascade hydrolysis/intramolecular SN2 process to close ring E, and a cascade intramolecular redox-ketalization process to close ring F. This synthesis would enrich the str...

The title compound C(23)H(29)NO(5), synthesized by the Amadori rearrangement of α-d-glucose with dibenzyl-amine and the ketalization, is shown to be a β-anomer. The fructopyran-ose ring adopts a chair conformation. The two benzene rings form a dihedral angle of 68.9 (1)°. In the crystal, non-classical inter-molecular C-H⋯O hydrogen bonds link the mol-ecules into a three-dimensional network.

Chemical investigations of Aquimarina sp. MC085, which suppressed TGF-?-induced epithelial–mesenchymal transition (EMT) in A549 human lung cancer cells, led to the isolation compounds 1–3. Structural characterization using spectroscopic data analyses combination with Marfey’s analysis revealed that they were two diketopiperazines [cyclo(l-Pro-l-Leu) (1) and cyclo(l-Pro-l-Ile) (2)] one N-pheneth...

Increasing the molecular accumulation and density of high-energy substances have a determinative role in improving the performance and intensity of energy release. Therefore, it is possible to increase the density of high-energy materials if the high-energy molecules can be arranged around a metal core as coordinated molecules. The aim of this project was to synthesize energetic complexes of cy...

Background: According to highlighted role of men in family planning, the use of reversible methods of contraception with no adverse effects on androgen-dependent metabolic reactions is very important. Therefore, in order to achieve a conductor combination in the designing contraceptive drugs, in the study, the effect of two drugs: Propylene glycol and Cyclo Hexyl on histological parameters of s...

To solve the problem of delivering pharmacologically promising 3ʹ,5ʹ-cyclic diadenosine monophosphate (cyclo-diAMP) to target cells in humans and animals, complexes above-mentioned dinucleotide with natural polymer – chitosan were originally synthesized by ionotropic gelation technique. It was found that binding degree cyclo-diAMP this biopolymeric carrier reaches 60 %; wherein capacity obtaine...