Two convenient methodologies have beendescribed for the enantiospecific synthesis of (–)-valeranone 1. The hydrindanone 12, obtained from the readily andabundantly available monoterpene (R)-carvone,has been converted into the ketoaldehyde 16via the alkene 15b. In anotherdirection the lactone 18, obtainedfrom the hydrindanone 12, has beenelaborated into the ketoaldehyde 16employing two methodolo...

Diastereoselective formal synthesis of a monoterpene alkaloid, (-)-incarvilline, the key intermediate for the synthesis of (-)-incarvillateine, was achieved by using an intramolecular Pauson-Khand reaction of (S)-N-[(E)-2-butenyl]-N-(3-butynyl-2-methoxymethoxy)-p-toluenesulfonamide as a key step.

Paeonins A and B, new monoterpene galactosides have been isolated from the chloroform-soluble fraction of the roots of Paeonia emodi and showed potent lipoxygenase inhibitory activity. The structures of 1 and 2 have been assigned on the basis of spectral analysis including one- and two-dimensional NMR techniques.

The methanolic extract of the aerial parts of Adenocaulon himalaicum (Asteraceae) has yielded a new acetylene, 1-O-feruloyl-tetradeca-4E,6E,12E-triene-8,10-diyne (1), a new monoterpene glycoside, 9-hydroxylinaloyl-3-O-(4-O-coumaroyl)-beta-D-glucopyranoside (2), and eight known compounds. Their structures were established by chemical and spectroscopic methods.

The structure of altemicidin, a new acaricidal and antitumor agent, was determined to be (1R,2S,3aR,7aS)-4-carbamoyl-2-hydroxy-6-methyl-1-(sulfamo ylacetamido)-2,3,3a,6, 7,7a-hexahydro-6-azaindene-1-carboxylic acid by a combination of spectroscopic and X-ray crystallographic analysis of its derivatives. Altemicidin is a monoterpene alkaloid.

Two new actinidine-type monoterpene alkaloids, delavayines B (1) and C (2), were isolated from the MeOH extract of the aerial parts of Incarvillea delavayi, a close species of which, I. sinensis, is used as an analgesic for rheumatic pain in China, and the structures have been elucidated on the basis of spectroscopic evidence.

Detoxification of an antifungal monoterpene terpinolene (1) by the plant pathogenic fungus Botrytis cinerea afforded hydroxlyated metabolites 2,3-dihydro-3beta,6beta-dihydroxy-terpinolene (2) (39%) and 2,3-dihydro-1alpha,3alpha-dihydroxy-terpinolene (3) (20%), respectively. Terpinolene showed good levels of antifungal activity while both the metabolites were inactive against another plant patho...

The absolute stereochemistry of rhodiolosides A-D (1-4), four monoterpene glycosides from the roots of Rhodiola rosea, and their aglycones, rhodiolol A (5), (-)-rosiridol (6) and sachalinol A (7), were reinvestigated. It was found that the absolute configurations of C-4 in these compounds, previously assigned to be 4-R, should be revised to 4-S.