4522-04-7Relevant articles and documents
Kendarimide A, a novel peptide reversing P-glycoprotein-mediated multidrug resistance in tumor cells, from a marine sponge of Haliclona sp.
Aoki, Shunji,Cao, Liwei,Matsui, Kouhei,Rachmat, Rachmaniar,Akiyama, Shin-Ichi,Kobayashi, Motomasa
, p. 7053 - 7059 (2004)
A novel modulator of multidrug resistance (MDR) in tumor cells, kendarimide A (1), was isolated from an Indonesian marine sponge of Haliclona sp. Compound 1 reversed MDR in KB-C2 cells mediated by P-glycoprotein (P-gp) at a 6 μM concentration, and the chemical structure of 1 was characterized to be a linear peptide composed of N-methylpyroglutamic acid (pyroMeGlu), N-methylated eight-membered cysteinyl-cysteine (ox-[MeCys-MeCys]) together with many N-methyl amino acid residues. The amino acid sequence of 1 was determined by 2D NMR and FAB MS analysis. The absolute configuration of the amino acid residues in 1 except for the MeCys part was determined to be L-form respectively, based on interpretation of the HPLC analysis of Marfey's derivatives of the hydrolysates of 1 and the synthetic method for the pyroMeGlu residue.
A (1 R, 3 S) -3 - amino-cyclopentanol hydrochloride preparation method (by machine translation)
-
, (2019/05/08)
The invention discloses a (1 R, 3 S) - 3 - amino-cyclopentanol hydrochloride of the preparation method, the method using chiral carboxylic acid with hydroxylamine to form the amide as chiral source, in copper catalyzed oxidation in the reaction system to rapidly obtain a chiral Diels - alder reaction product, after passes through the reduction reaction and alkaline deprotection reaction, and acidified after reaction to obtain the target product. Chiral inducing reagent chiral carboxylic acid by simple acidification, extraction processing can be reclaimed and reused. This kind of (1 R, 3 S) - 3 - amino-cyclopentanol hydrochloride preparation method has high operation safety and high selectivity, raw materials are easy, and the cost is low, the reaction time is short and simple process flow and the like. (by machine translation)
Ring opening reactions of cyclic sulfamidates. Synthesis of β-fluoroaryl alanines and derivatives of 4,4-difluoroglutamic acid
Bolek, Sylwia,Ignatowska, Jolanta
, p. 13 - 21 (2018/11/24)
Ring opening reactions of 1 with copper complex formed between Cu, TMEDA and BrCF2CO2Et lead to optically active 4,4-difluoroglutamic acid derivatives 11a-d in moderate yields. Reaction of cyclic sulfamidates 1 with fluoro substituted arylmagnesium chlorides proceed via copper catalyzed 1,4-addition of Grignard reagent to dehydroalanine 2, formed in situ. Fluorinated organoznic derivatives were unreactive towards 1 regardless of the reaction conditions; instead product of reaction of 1 with DMF was isolated.