Total Solid Phase Syntheses of the Quinazoline Alkaloids: Verrucines A and B and Anacine
摘要:
The first total syntheses of verrucines A and B and anacine (revised structure) were accomplished on Sasrin resin. This work confirmed the structure of verrucine A and unambiguously showed verrucine B to be a derivative of D-phenylalanine and L-glutamine, The study also proved that anacine and its epimer are quinazoline alkaloids, not benzodiazepines as originally proposed. 1-Hydroxyverrucine B, derived from air oxidization of verrucine B, was also isolated and characterized.
Eco-Friendly Synthesis of Peptides Using Fmoc-Amino Acid Chlorides as Coupling Agent Under Biphasic Condition
作者:Santosh Y. Khatavi、Kamanna Kantharaju
DOI:10.2174/0929866527666201119161116
日期:2021.6.25
Fmoc-amino acid chloride gave final product dipeptide ester in good to excellent yields. The protocol occurs with complete stereo chemical integrity of the configuration of substrates. Here, we revisited Schotten-Baumann condition, instead of using inorganic base. Objective: To develop green protocol for the synthesis of peptide bond using Fmoc-amino acid chloride with aminoacid esters salt. Methods: The
There is provided a range of novel compounds. These novel compounds may demonstrate a broad spectrum antibacterial and antifungal activity. These compounds may be active against the emerging polymyxin resistant bacteria. These compounds may also be useful when used in conjunction with other pharmaceutically active agents.
The synthesis of the uncommon dihydropyrazinone ring was accomplished by a two-step one pot process taking advantage of the ring rearrangement of N-acylated morpholine acetal derived from serine under acidic treatment in the presence of 2,6-lutidine. The mechanism involves an N-acyl iminium intermediate resulting from morpholine acetal ring opening, which occurs after a nucleophilic attack of the amino
Design of a new peptidomimetic agonist for the melanocortin receptors based on the solution structure of the peptide ligand, Ac-Nle-cyclo[Asp-Pro-dPhe-Arg-Trp-Lys]-NH2
作者:Christopher Fotsch、Duncan M Smith、Jeffrey A Adams、Janet Cheetham、Michael Croghan、Elizabeth M Doherty、Clarence Hale、Mark A Jarosinski、Michael G Kelly、Mark H Norman、Nuria A Tamayo、Ning Xi、James W Baumgartner
DOI:10.1016/s0960-894x(03)00412-8
日期:2003.7
The solutionstructure of a potent melanocortin receptor agonist, Ac-Nle-cyclo[Asp-Pro-DPhe-Arg-Trp-Lys]-NH(2) (1) was calculated using distance restraints determined from 1H NMR spectroscopy. Eight of the lowest energy conformations from this study were used to identify non-peptide cores that mimic the spatial arrangement of the critical tripeptide region, DPhe-Arg-Trp, found in 1. From these studies
(Fluoren-9-ylmethoxy)carbonyl (Fmoc) amino acid chlorides. Synthesis, characterization, and application to the rapid synthesis of short peptide segments
作者:Louis A. Carpino、Beri J. Cohen、Kenton E. Stephens、S. Yahya Sadat-Aalaee、Jien Heh Tien、Denton C. Langridge