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At least 19 recordsLinked to original sources
PubMed1980

Configurational assignments to spirostan-3-ols by mass spectrometry.

A study of the degree of water elimination from ions derived from spirostan-3-ols by electron bombardment has shown that the loss is greatest from those ions produced by the 5 beta-spirostan-3 alpha-ols, less from the 5 beta-spirostan-3 beta-ols and the 5 alpha-spirostan-3 alpha-ols, which give losses of the same order of magnitude; and least from the 5 alpha-spirostan-3 beta-ols. The extent of water elimination can be used to help characterise spirostan-3-ols isolated from plant materials.

Chemical Phenomena↗
PubMed1991

A spirostane hexaglycoside from Agave cantala fruits.

A new steroidal glycoside, agaveside D, isolated from the fruits of Agave cantala was characterized as 3 beta-(alpha-L-rhamnopyranosyl-(1----2),beta-D-glycopyranosyl- (1----3)-beta-D-glucopyranosyl[beta-D-xylopyransoyl-(1----4)-alpha -L-rhamnopyranosyl-(1----2)]-beta-D-glucopyranosyl)-25R-5 alpha-spirostane on the basis of chemical degradation and spectrometry.

Carbohydrate Sequence↗
PubMed2002

Spirostanic analogues of castasterone.

The synthesis, spectroscopic characterization, and biologic activity of two bioactive spirostanic analogues of the naturally occurring brassinosteroid castasterone are described.

Borohydrides↗
PubMed2002

A convenient synthesis of C-22 and C-25 stereoisomers of cephalostatin north 1 side chain from spirostan sapogenins.

A simple transformation of the eight-carbon side chain of a natural spirostan sapogenin into the cephalostatin north 1 spiroketal moiety is described. This methodology, based on an intramolecular hydrogen abstraction reaction promoted by alkoxy radicals, permits the synthesis of C-22 and C-25 stereoisomers of the dioxaspiro[4.4]nonane cephalostatin ring system. The acid-catalyzed isomerization of the spirocenter in the different isomers is studied. [reaction: see text]

Crystallography, X-Ray↗
PubMed1998

Carbohydrate modifications in the spirostane cellobioside cholesterol absorption inhibitor series.

Cholesterol absorption inhibition remains an attractive approach for the treatment of hypercholesterolemia. We have continued our SAR development in the spirostanyl cellobioside class of agents seeking a greater understanding of the role carbamoyl substitution has on the potency in this series. In this regard, a series of differentially substituted carbamate analogs were made with and without deoxygenations. From this study, it was determined that the minimal requirements for optimal potency was a lone carbamate at C4" and deoxygenation at the C6" position.

Anticholesteremic Agents↗
PubMed2002

An assisted solvolysis of 23-spirostanyl bromides and tosylates. A new rearrangement of spirostanes to the bisfuran systems.

Steroidal sapogenins bearing a good leaving group at C23 undergo a completely stereospecific rearrangement under a variety of conditions via a mechanism involving neighboring-group participation by the acetal oxygen atom in the departure of the nucleofuge from C23. The reactions of equatorial (23S)-23-bromo- or (23S)-23-tosyloxyspirostanes with either the alpha (25R) or beta (25S) oriented 25-methyl group lead to the bisfuran products with inversion of configuration at C23. The reactions of the starting compounds with axial substituents (23R) at C23 require drastic conditions and result in the formation of the corresponding olefin accompanied by the rearranged product (in the case of the 25S isomer only).

Combinatorial Chemistry Techniques↗
PubMed2001

SC-1, an antimycotic spirostan saponin from Solanum chrysotrichum.

A new antimycotic steroidal saponin named SC-1 has been isolated from the leaves of Solanum chrysotrichum by bioassay-guided fractionation. The structure of SC-1 was characterized as 3-O-[beta-quinovopyranosyl(1-->6)-beta-glucopyranosyl(1-->6)-beta- glucopyranosyl]chlorogenin on the basis of spectral analyses and chemical evidence.

Antifungal Agents↗