31570-39-5Relevant articles and documents
Mechanistic investigations on multiproduct β-himachalene synthase from Cryptosporangium arvum
Rinkel, Jan,Dickschat, Jeroen S.
supporting information, p. 1008 - 1019 (2019/06/08)
A bacterial terpene synthase from Cryptosporangium arvum was characterised as a multiproduct β-himachalene synthase. In vitro studies showed not only a high promiscuity with respect to its numerous sesquiterpene products, including the structurally demanding terpenes longicyclene, longifolene and α-longipinene, but also to its substrates, as additional activity was observed with geranyl- and geranylgeranyl diphosphate. In-depth mechanistic investigations using isotopically labelled precursors regarding the stereochemical course of both 1,11-cyclisation and 1,3-hydride shift furnished a detailed catalytic model suggesting the molecular basis of the observed low product selectivity. The enzyme's synthetic potential was also exploited in the preparation of sesquiterpene isotopomers, which provided insights into their EIMS fragmentation mechanisms.
Studies on macrocyclic diterpenoids (XVII): Total synthesis of (-)-cembrene-A and (+)-3,4-epoxycembrene-A by titanium-induced carbonyl coupling reactions
Yue, Xiangjun,Li, Yulin
, p. 736 - 740 (2007/10/03)
Efficient total syntheses of (R)-cembrene-A (1) and (+)-3,4-epoxycembrene-A (2), two marine cembranoids, starting from (E)-geranylacetone (6) and (R)-limonene (7) are described. The key steps are the synthesis of olefin 12 from phosphonate 4 and optically active ketone 5 by the modified Wittig olefination, and the titanium-induced intramolecular coupling of oxo aldehyde 3 to afford cembrene-A (1). The pinacol coupling of 3 yielded the diol 13 which was converted into 3,4-epoxycembrene-A (2).
Novel Synthesis of (-)-(R)-Cembrene A, Synthesis of (+)-(R)-Cembrenene and (+)-(S)-Cembrene
Farkas, Imre,Pfander, Hanspeter
, p. 1980 - 1985 (2007/10/02)
A novel synthesis of (-)-(R)-cembrene A ((-)-3) was developed using the Sharpless epoxidation for the introduction of the chiral center.Furthermore, the synthesis of (+)-(R)-cembrenene ((+)-4) showed that this cembranoid must have the (R)-configuration and not, as previously reported, the (S)-confguration.Selective hydrogebation of (+)-4 afforded (+)-(S)-cembrene ((+)-5).
PREPARATION OF ENANTIOMERICALLY PURE 1-HYDROXY-NEOCEMBRENES TO DETERMINE THE UNSOLVED ABSOLUTE CONFIGURATION OF CEMBRENOIDS
Aoki, Mario,Uyehara, Tadao,Kato, Tadahiro,Kabuto, Kuninobu,Yamaguchi, Shozo
, p. 1121 - 1124 (2007/10/02)
Cis and trans 1-hydroxy-neocembrenes were prepared in an enantiomerically pure form by reduction of dl-ketone with respective (+)- and (-)-Darvon-LiAlH4 complex followed by purification with the aids of esterification with d- and l-menthoxyacetyl chlorides and (-)-camphanic acid chloride, respectively.Absolute configuration of naturally occurring (+)-mayol and (+)-cembrenene was determined by correlation with enantiomerically pure compounds.
Studies of Australian Soft Corals. XXIV. Two Cembranoid Diterpenes from the Soft Coral Sinularia facile
Bowden, Bruce F.,Coll, John C.,Mitchell, Sarah Jane,Kazlauskas, Rymantas
, p. 1551 - 1556 (2007/10/02)
Extraction of the soft coral Sinularia facile afforded two cembranoid diterpenes whose structures and absolute configurations have been determined as (1R,4R,2E,7E,11E)-cembra-2,7,11-trien-4-ol (1) and (1R,3S,4S,7E,11E)-3,4-epoxycembra-7,11,15-triene (2).
