Asymmetric .ALPHA.-substituted phenethylamines. I. Synthesis of optically pure 1-aryl-N-(2'-hydroxy-1'-isopropylethyl)-2-phenylethylamines.
作者:HIROSHI TAKAHASHI、YUJI SUZUKI、HIDEKAZU INAGAKI
DOI:10.1248/cpb.30.3160
日期:——
Optically pure 1-aryl-N-(2'-hydroxy-1'-isopropylethyl)-2-phenylethylamines (3a-c) were synthesized by the reactions of N-(2-hydroxy-1-isopropylethyl) arylmethylideneamines (2a-c) with benzylmagnesium chloride. The diastereomers (5a-c) were prepared from N-(2-hydroxy-1-isopropylethyl) phenylethylideneamine (4) and aryllithium compounds. The optical purity of 3a was elucidated and the absolute configuration was determined by synthesis via an alternative route. The characteristic methyl signals in the nuclear magnetic resonance (NMR) spectra suggested the configurations of the chiral amines (3a-c and 5a-c).
Synthesis of L-Prolyl-leucyl-α-aminoisobutyryl-α-amino-isobutyryl-glutamyl-valinol and Proof of Identity with the Isolated C-Terminal Fragment of Trichotoxin A-40
作者:Hans Brückner、Günther Jung
DOI:10.1002/jlac.198219820909
日期:1982.9.17
tamyl-[or L-glutaminyl-, respectively]L-valinol (7 and 8) were synthesized via fragment condensation of Z-L-Pro-L-Leu-Aib-Aib-OH (5a) with L-Glu(But)-Vol (9b) [or L-Gln-Vol (10), respectively]. The synthetic segment 7 was found to be identical with a C-terminalfragmentisolated from selectively cleaved trichotoxinA-40 using thin layer chromatography, amino acid analysis, chiral phase gas chromatography
两个六肽-L-脯氨酰基-L-亮氨酰基- α-aminoisobutyryl-α-aminoisobutyryl-L-谷氨[或L-glutaminyl-,分别] L-缬氨醇(7和8)的合成经由ZL-亲的片段缩合具有L-Glu(Bu t)-Vol(9b)[或分别为L-Gln-Vol(10)的L-Leu-Aib-Aib-OH(5a)]。使用薄层色谱法,氨基酸分析,手性气相色谱法,现场解吸质谱法,发现合成片段7与从选择性裂解的滴虫毒素A-40中分离出的C端片段相同,1313 C NMR光谱和圆二色性。通过天然Pro-Leu-Aib-Aib [Iva] -Glu-Vol(7a和7b)和合成Pro-Leu-Aib-Aib-Glu-Vol的选择性三氟乙酰水解显示了C端氨基醇的α键(7)并与合成的Glu-Vol(9),Gln-Vol(10),Glu(Vol)(11)和Glu(Vol)-NH 2(12)进行
Heteroaryl sulfonamide synthesis: scope and limitations
作者:Roman O. Iakovenko、Daniel Chrenko、Jozef Kristek、Eline Desmedt、František Zálešák、Freija De Vleeschouwer、Jiří Pospíšil
DOI:10.1039/d2ob00345g
日期:——
Heteroaryl sulfonamides are important structural motifs in the medicinal and agrochemical industries. However, their synthesis often relies on the use of heteroaryl sulfonyl chlorides, which are unstable and toxic reagents. Herein, we report a protocol that allows direct oxidative coupling of heteroaryl thiols and primary amines, readily available and inexpensive commodity chemicals. The transformation