<i>S</i>- to<i>N</i>-Acyl transfer in<i>S</i>-acylcysteine isopeptides via 9-, 10-, 12-, and 13-membered cyclic transition states
作者:Oleg Bol'shakov、Judit Kovacs、Mamta Chahar、Khanh Ha、Levan Khelashvili、Alan R. Katritzky
DOI:10.1002/psc.2438
日期:2012.11
S‐Acyl cysteine peptides containing α‐, β‐ or γ‐amino acid residues undergo long‐range S‐ to N‐acyl transfer to give analogs of native tripeptides and tetrapeptides containing additional carbon atoms in the chain. The ease of intramolecular S → N‐acyl transfer relative to intermolecular transacylation is favored increasingly for 9 < 12 < 13 ~ 10‐membered cyclic transition states; the observed order
Ligations from Tyrosine Isopeptides via 12- to 19-Membered Cyclic Transition States
作者:Vadim Popov、Siva S. Panda、Alan R. Katritzky
DOI:10.1021/jo4009468
日期:2013.8.2
Efficient syntheses of O-acyl Tyr-peptides allow chemical long-range ligation (O-acyl to N-acyl transfer) via each of 12- to 19-membered cyclictransitionstates. The results represent the first examples of successful isopeptideligations starting fromO-acyl Tyr-peptides.
Synthesis and molecular modeling of antimicrobial active fluoroquinolone–pyrazine conjugates with amino acid linkers
作者:Siva S. Panda、Oleksandr S. Detistov、Adel S. Girgis、Prabhu P. Mohapatra、Ahmed Samir、Alan R. Katritzky
DOI:10.1016/j.bmcl.2016.03.062
日期:2016.5
Novel fluoroquinolone–pyrazine conjugates 7a–h with aminoacid linkers were synthesized in good yields utilizing benzotriazole chemistry. Antimicrobial bioassay showed that the synthesized bis-conjugates have antimicrobial properties comparable to the parent drugs. Compound 7h showed superior antibacterial activity against Staphylococcus aureus and Streptococcus pyogenes (MIC = 74.6 μM and 149.3 μM
Ligations of N-acyl tryptophan units to give native peptides via 7-, 10-, 11- and 12-membered cyclic transition states
作者:Vadim Popov、Siva S. Panda、Alan R. Katritzky
DOI:10.1039/c3ob27421g
日期:——
N-Acyl tryptophan isopeptides undergo acyl transfer in chemicalligationsvia 7-, 10-, 11- and 12-membered cyclictransitionstates to yield natural peptides, representing the first examples of successful isopeptideligationsfrom N-acyl tryptophan units.
Ligations of O-acyl threonine units to give native peptides via 5-, 8-, 9- and 10-membered cyclic transition states
作者:Siva S. Panda、Sumaira Liaqat、Anand D. Tiwari、Hadi M. Marwani、Hassan M. Faidallah、Abdul Rauf、C. Dennis Hall、the late Alan R. Katritzky
DOI:10.3998/ark.5550190.p008.796
日期:——
N-Acyl threonine isopeptides undergo acyl transfer in chemical ligationsvia5-, 8-, 9and 10membered cyclictransitionstates to yield natural peptides, representing the first examples of successful isopeptide ligations from N-acyl threonineunits.