Structures of rengyosides A, B and C, three glucosides of Forsythia suspensa fruits
作者:Kazuhiko Seya、Katsuya Endo、Hiroshi Hikino
DOI:10.1016/s0031-9422(00)97772-0
日期:——
glucosides, rengyosides A, B and C, having as aglycones the reduced forms of phenylethanol were isolated from Forsythia suspensa fruits. Chemical and spectroscopic studies established the structures of these natural products to be 2-(1,4-dihydroxycyclohexyl)ethyl β- d -glucopyranoside, 2-(1-hydroxy-4-ketocyclohexyl)ethyl β- d -glucopyranoside and 2-(1,4-dihydroxycyclohexyl)ethyl β- d -6-O-[2-(4-hydroxypheny
Rengyol and seven related cyclohexylethanoid natural products have been synthesized in a stereocontrolled manner from a common starting material. In the present study the absolute configuration of the three chiral products has been determined and the first synthesis of a cyclohexylethanoid natural product bearing an oxetane ring has been accomplished.
Stereostructure of Rengyol and Isocengyol, Phenylethanoids of
作者:Katsuya Endo、Kazuhiko Seya、Hiroshi Hikino
DOI:10.1016/s0040-4020(01)86873-3
日期:1987.1
4-acetoxycyclohexanone with ethyl bromoaoetate afforded two isomeric acetoxy esters (5, 6) and the one (5) which has an equatorial acetoxy1 group yielded on IAH reduction a triol identified as rengyol (1). The isomer (7), obtained similarly from the other isomeric acetoxy ester (6), has also been isolated from the natural source and is named isorengyol. Further, dehydration of the esters (5,6) and subsequent
已经描述了通过合成方法测定rengyol(1)的立体结构的方法,rengyol(1)是从连翘中分离得到的一种新型非芳族苯乙醛类天然产物。4-乙酰氧基环己酮与溴代乙酸乙酯的Reformatsky反应提供了两种异构体的乙酰氧基酯(5,6),以及一种通过IAH还原生成的具有赤道乙酰氧基的基团(5)的三醇被鉴定为rengyol(1)。类似地从另一种异构体乙酰氧基酯(6)获得的异构体(7)也已从天然来源中分离出来,并被命名为异戊二醇。进一步地,将酯类(5,6)脱水,然后进行热解脱乙酰氧基化,得到1,3-环己二烯衍生物(12),将其在光敏的顺式-二加氧作用下还原,得到苯二酚(1),其立体结构确定为1, 4-顺-环己二醇体系。1 H和13 C NMR光谱数据。
Cyclohexyl-ethanol derivatives from Isoplexis chalcantha
作者:Eduardo Navarro、Juan Trujillo、Jose L. Breton、Jose Boada
DOI:10.1016/s0031-9422(00)81193-0
日期:1986.7
Abstract Two new cyclohexyl-ethanol derivatives were obtained as minor components from a chloroform extract of the leaves of Isoplexischalcantha . Their structures were elucidated by spectroscopic methods.