1,7-Cyclogermacra-1(10),4-dien-15-al, a sesquiterpene with a novel skeleton, and other sesquiterpenes from Haitian vetiver oil

Total Synthesis of (+)-Prezizaan-15-ol, (+)-Jinkohol II, and (+)-Jinkoholic Acid

“…The NMR data of the natural product as provided by Nakanishi et al match perfectly with the synthetic product 3b but not with the compound with structure 3a . The latter compound was confirmed to be (+)-prezizaan-15-ol . The specific rotation of 3b was determined as +32 ( c = 0.26, CHCl 3 ) and was identical with the reported value for (+)-jinkohol II.…”

“…In 2020, Weyerstahl et al pointed out, in a comprehensive publication on sesquiterpenes from Haitian vetiver oil, that the 1 H NMR data of compounds 3a and 3b are very similar while they differ significantly in their 13 C NMR spectra. Based on semisynthetic work, they suggested to assign structure 3b to jinkohol II and renamed 3a prezizaan-15-ol . Likewise, the respective jinkoholic acid, which had been previously isolated from Neocallitropsis pancheri , was reported to display a specific rotation of [α] D 20 = +26 ( c = 0.41, CHCl 3 ) and was proposed to be compound 4 .…”

Characterization of a silent sesquiterpenoid biosynthetic pathway in Streptomyces avermitilis controlling epi‐isozizaene albaflavenone biosynthesis and isolation of a new oxidized epi‐isozizaene metabolite

“…Analysis of the genome sequences of S. coelicolor A3(2) and S. avermitilis has revealed addional terpene synthases encoding the biosynthesis of germacradienol and geosmin (responsible for the characteristic smell of moist soil) and of epi -isozizaene and the derived antibiotic albaflavenone. Zizaene-type volatiles are well-known as constituents of vetiver root essential oil from Vetiveria zizanioides (Poaceae) (Weyerstahl et al ., 2000). The earthy odorant and antibiotic albaflavenone ( 3 ) was first isolated 1994 from S. albidoflavus (Gütler et al ., 1994) while the parent sesquiterpene hydrocarbon, epi -isozizaene ( 1 ), was first identified 2006 as a result of genome mining of S. coelicolor A3(2), in which recombinant enzyme from S. coelicolor A3(2) and expressed in E. coli was shown to catalyze the Mg 2+ -dependent cyclization of farnesyl diphosphate epi -isozizaene ( 1 ) (Lin et al ., 2006; Lin et.…”

Integrated Analysis of the Bark Oil from Cinnamosma madagascariensis by GC(RI), GC-MS and NMR. 13C NMR data of Cyclocopacamphene and Cyclosativene

“…Unfortunately, the 13 C NMR data were not reported. However, comparison of the 13 C NMR chemical shifts of our compound with those of cyclocopacamphan-12-ol [14] was informative. Indeed, 11 out of 15 carbon chemical shifts of our unidentified component were very close to those of cyclocopacamphan-12-ol; they differed by 0.0-0.2 ppm for 10 carbons, and 0.4 ppm for the last one.…”