A base labile protecting group for peptide synthesis: 2,2 -Bis(4′-nitrophenyl)ethan-1-oxycarbonyl urethanes
摘要:
A base labile urethane (Bnpeoc) group derived from 2,2-bis(4'-nitrophenyl)ethan-1-ol has been developed as an amine protecting group. This protecting group may be cleaved using the reagents, DBN, DBU, DBU/HOAc and piperidine. The preparations of N-alpha-Bnpeoc amino acids and applications to peptide/glycopeptide synthesis are described.
The substituent effect on the acetolysis of 2,2-bis(substituted phenyl)ethyl p-toluenesulfonates at 90.10 °C can be described accurately in terms of the Yukawa–Tsuno (LArSR) relationship, giving a ρ value of −4.44 and an r value of 0.53. The substituent effect correlation of this system carrying two aryls is quite comparable to that of the 2-methyl-2-phenylpropyl system carrying a single aryl group, suggesting the close similarity in the structure of the transition states between the systems. The results can be reasonably accounted for on the basis of the accepted mechanism of this reaction, involving a rate-determining aryl-assisted transition state where only one aryl group of the two β-aryl groups participates.
This invention relates to a range of alpha substituted 2-benzyl substituted imidazole compounds and pharmaceutically acceptable salts and solvates thereof, to compositions comprising such compounds, processes for their synthesis and their use as parasiticides.
The present application provides compounds of Formula (B):
or pharmaceutically acceptable salts thereof, wherein D is a residue of a biologically active drug, which underdo hydrolysis under physiological conditions to release the biologically active drug and which are useful in the treatment of disorders that could be beneficially treated with the drug.
本申请提供了式 (B) 的化合物:
或其药学上可接受的盐,其中 D 是生物活性药物的残留物,在生理条件下可水解释放出生物活性药物,可用于治疗可使用该药物进行有益治疗的疾病。
Studies on the reaction of 3,3,4,4-tetraphenylthietan-2-one
作者:P. Charumilind、Harold Kohn
DOI:10.1021/jo01310a019
日期:1980.10
Preparation of 2-phenylethanol and 2-phenylethyl acetate