Structures of angrendiol, ferolin, and chimganidin
SummaryOn the basis of the results of a study of the products of chemical transformations and spectra, the structure of angrendiol has been established as 4,8-dihydroxygermacra-1(10), 5(6)-diene. It has been shown that ferolin and chimganidin are monoesters of angrendiol with parahydroxybenzoic and vanillic acids, respectively, at the secondary hydroxy group.
Terpenoids—L : Transformation products of costunolide
Abstract Costunolide, containing a ten-membered carbocyclic ring system with the unique distribution of double bonds, undergoes many interesting transformations. The diol prepared by lithium aluminium hydride reduction of costunolide when subjected to metal amine reduction gives a hydrocarbon, C15H26, a secondary alcohol, C15H26O, and a primary alcohol, C15H26O, and a primary alcohol, C15H26O to which structures, VIII, X and XII have been assigned on the basis of spectral data and their conversions to elemene-type products on pyrolysis and to mono-ethenoid bicyclic products on acid catalysed cyclization. The secondary alcohol X has been converted to d -junenol which constitutes a new synthesis of the alcohol from costunolide. Pyrolysis and acid catalysed cyclization of 12-methoxydihydrocostunolide have also been described.
Terpenoids—XXXII : Absolute configuration of junenol and laevojunenol and synthesis of junenol from costunolide
Abstract The North Indian vetiver variety has yielded a new laevo-rotatory crystalline sesquiterpene alcohol, which is named as laevojunenol. It is the optical antipode of the previously isolated dextrorotatory alcohol, junenol. The absolute configuration of these two alcohols, which belong to eudesman group of compounds has been determined on the basis of the synthesis of dihydrojunenol from santanolide ‘c’. The dextrorotatory alcohol junenol has also been similarly synthesized from the new unsaturated lactone (XII), derived from the ten-membered carbocyclic lactone costunolide.