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D J Slatkin

Publications and source records attributed to D J Slatkin.

25 records · Page 2Linked to original sources
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A constituent of Pterocarpus marsupium, (-)-epicatechin, as a potential antidiabetic agent.

An active constituent of Pterocarpus marsupium, (-)-epicatechin (1), has been reported to reverse hyperglycemia in alloxan diabetic rats when given before or within 24 hr after the dose of alloxan. However, when doses of (-)-epicatechin (30 mg/kg, i.p., twice daily for 3 days) are begun 92 hr after alloxan, there is no significant difference in blood glucose levels between control and (-)-epicatechin treated rats. These data suggest that, although (-)-epicatechin may protect against alloxan toxicity under certain conditions, the usefulness of (-)-epicatechin appears minimal in the treatment of already established diabetic states.

Animals↗
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Additional alkaloids of Pachygone ovata.

Pachygone ovata (Menispermaceae), indigenous to the sandy seashores of southern India, is a woody climber whose fruits have been used as a rodenticide and fish poison. Chromatography of the extract of the roots resulted in the reisolation of the alkaloids liriodenine, coclaurine, trilobine (1), and magnoflorine and the isolation of stepholidine, coreximine, isoboldine, norjuziphine, and nortrilobine (2). Nortrilobine (2) is a new dibenzo-p-dioxin bisbenzylisoquinoline alkaloid whose structure was established by a consideration of spectral data and conversion to isotrilobine (3).

Alkaloids↗
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Metabolites of aspergilli. II. Asparvenone and O-methylasparvenone, naphthalenones from Aspergillus parvulus.

When grown on a malt extract-glucose medium, Aspergillus parvulus Smith (ATCC "169911) produced at least four metabolites detectable on thin-layer plates with ferric chloride spray. Two of these metabolities, asparvenone (7-ethyl-3,4-dihydro-4,6,8-trihydroxy-1(2H)-naphthalenone) and O-methylasparvenone (7-ethyl-3,4-dihydro-4,8-dihydroxy-6-methoxy-1(2H)-naphthalenone), were isolated and their structures determined. The structure of O-methylasparvenone was determined by chemical and spectral means and X-ray crystallographic studies of its monoacetate. The structure of asparvenone was deduced by spectral and chemical means and by methylation with diazomethane to O-methylasparvenone.

Aspergillus↗
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Constituents of West African medicinal plants. XXI. Tiliafunimine, a new imino bisbenzylisoquinoline alkaloid from Tiliacora funifera.

Tiliacora funifera (Menispermaceae) is a woody climber of Ghana and West Africa that has been used natively as a medicinal in the treatment of numerous ailments. Chromatography of an extract of the leaves of T. funifera afforded tiliafunimine (13) whose ir, uv, nmr, and mass spectra were characteristic of a trimethoxylated phenolic iminobisbenzylisoquinoline alkaloid. Reduction of tiliafunimine with sodium borohydride afforded the dihydro-derivative (14) which upon treatment with formalin gave thalrugosine (12). The final structural assignment of tiliafunimine (13) as an iminobisbenzylisoquinoline alkaloid was made by nmr and mass spectral considerations. Other alkaloids isolated from the same extract include the bisbenzylisoquinoline bases isotetrandrine (11) and thalrugosine (12).

Chemical Phenomena↗
PubMedDate not supplied

DIOXINS/*ISOLof West African medicinal plants. XV. Dinklacorine, a new biphenyl dibenzodioxin alkaloid from Tiliacora dinklagei.

Dinklacorine was first isolated in 1974 from extracts of the roots of Tiliacora dinklagei Engl. (Menispermaceae) and designated TD-2. The ir, uv and mass spectra of dinklacorine were very similar to those of the dibenzodioxin biphenylalkaloid tiliacorine. However, the two alkaloids differed in their mp, specific rotation and nmr spectra. Methylation of dinklacorine with diazomethane afforded O-methyltiliacorine while treatment of dinklacorine with sodium methoxide and methyl iodide gave O-methyltiliacorine dimethiodide. However, prolonged treatment of tiliacorine and dinklacorine with diazoethane afforded different O-ethyl ethers. In addition, O-ethyldinklacorine dimethiodide and O-ethyltiliacorne dimethiodide were different. Furthermore, acetylation of the two alkaloids with acetic anhydride and puridine gave O-macetyl esters which were not identical. A considertation to these data and especially the mass spectral fragmentation patterns indicated dinklacorine to be a positional isomer of tiliacorine with the phenolic hydroxy group present in the biphenyl portion of the molecule on the opposite side to tiliacorine. Finally, a comparison of the cd spectra of dinklacorine and tiliacorine suggests that they have the same stereochemistry.

Alkaloids↗