Ent-2α-hydroxy-13-epi-manoyl oxide from Sideritis perfoliata

A new ent-13-epi-manoyl oxide derivative was isolated from the aerial part of Sideritis perfoliata. Its structure, ent-2α-hydroxy-8,13β-epoxy-labd-14-ene, was established by chemical and spectroscopic means.     

New diterpenes from Sideritis candicans

The three new diterpenes candol-A (ent-16-kauren-7α-ol, I), candol-B (ent-16-kauren-18-ol, III) and epicandicandiol 7β-monoacetate (ent-7α-acetoxy-16-kauren-18-ol, V) as well as epicandicandiol (VII) have been isolated from Sideritis candicans.     

Hypolaetin 8-glucoside from Sideritis leucantha

A new naturally occurring hypolaetin 8-β-D-glucoside has been isolated and identified from Sideritis leucantha. The natural compound suffered nuclear methylation during derivatization.     

New diterpenes from Sideritis canariensis

Two new diterpenes ribenol [3α-hydroxy-(?)-13-epimanoyl oxide] (I)and 7β-acetoxy-18-hydroxytrachylobane (IX) as well as the known (?)-13-epimanoyl oxide (IV) have been isolated from Sideritis canariensis Ait.     

Grayanotoxin-XVIII and grayanoside B,a new a-nor-b-homo-ent-kaurene and its glucoside from Leucothoe grayana

From Leucothoe grayana a new grayanoid (diterpene) and its glucoside have been isolated. The structures of these new natural compounds have been established by chemical and spectroscopic means and by correlation with a known compound.     

ent-Kauranoid derivatives from Sideritis moorei

Seven new ent-kauranoid derivatives ent-7alpha,18-dihydroxykaur-16-en-3-one, ent-18-acetoxy-3beta,7alpha-dihydroxykaur-15-en-17-al, ent-3beta-acetoxy-7alpha,18-dihydroxykaur-15-en-17-al, ent-18-acetoxy-3beta,7alpha,17-trihydroxykaur-15-ene, ent-3beta-acetoxy-7alpha,17,18-trihydroxykaur-15-ene, ent-18-acetoxy-3beta,7alpha,17-trihydroxy-15beta,16beta-epoxykaurane and ent-3beta-acetoxy-7alpha,17,18-trihydroxy-15beta,16beta-epoxykaurane have been isolated from Sideritis moorei. The structures of these compounds have been established by spectroscopic means and chemical correlations.     

Leucasin, a triterpene saponin from Leucas nutans.

A new saponin, leucasin, has been isolated from Leucas nutans and characterized on the basis of chemical investigation and spectroscopic studies as 3-O-[β- -glucopyranosyl(1→2)β- -glucopyranosyl]2,3β-dihydroxylup-20(29)-ene. Lupeol palmitate, sitosterol and stigmasterol were also isolated.     

New diterpenes from Sideritis sicula

Two new diterpenes have been isolated from Sideritis sicula: sideripol, ent-18-acetoxy-7α-hydroxykaur-15-ene and epoxysideritriol, ent-15β,16β-epoxykauran-7α,17,18-triol. The previously known diterpene eubol, ent-7α-acetoxykaur-16-en-15β,18 diol has also been obtained from the same source.     

Detailed analysis of metabolites from mevalonic lactone in Gibberella fujikuroi

Methods for the detailed analysis of diterpenoid metabolites from Gibberella fujikuroi are described. The metabolites from 2-[³H]-mevalonic acid lactone are separated by partition chromatography on Sephadex LH20 columns, detected by radio-counting and characterised by gas-chromatography directly linked to radio-counting and MS. From one fermentation, 72 compounds were detected. Of these, 25 known diterpenes, including 15 gibberellins, were identified and 7 new products were assigned tentative structures.     

Diterpenes from sideritis nutans

Four new ent-labdane oxide diterpenes, sidnutol, gomerol, 13-epi-gomerol and 3α-hydroxy-gomeric acid, and the previously known gomeraldehyde, 13-epi-gomeraldehyde, ent-norambreinolide, ent-2α-hydroxy-13-epi-manoyloxide, gomeric acid and 13-epi-gomeric acid, have been isolated from the aerial parts of Siderius nutans.     

Four new diterpenes from Sideritis serrata

Four new diterpenes have been isolated from Sideritis serata: lagascol (4, ent-8,5-friedopimar-5-ene-15S,16-diol), tobarrol (8, ent-15-beyerene-12α,17-diol), benuol (12, ent-15-beyerene-7α,17-diol) and serradiol (18, ent-16R-atis-13-ene-16,17-diol). The previously known diterpenes lagascatriol (1, ent-8,5-friedopimar-5-ene-11β,15S,16-triol), jativatriol (2, ent-15-beyerene-1β,12α,17-triol), conchitriol (3, ent-15-beyerene-7α,12α,17-triol) and sideritol (17, ent-16R-atis-13-ene-1β,16,17-triol) have also been obtained from the same source.     

Diterpenoid quinones of Salvia lanata

The petrol extract of the whole plant (aerial parts and roots) of Salvia lanata yielded three diterpenoid quinones of the royleanone type, identifi