The roots of Salvia rhytidea: a rich source of biologically active diterpenoids.

Sahandinone (1), 12-deoxysalvipisone (2), miltirone (3), 7α-acetoxyroyleanone (4), and labda-7,14-dien-13-ol (5) were isolated from the roots of Salvia rhytidea Benth. (Lamiaceae). Their structures were elucidated by a combination of spectroscopic analyses including EIMS and NMR. The 13C NMR spectroscopic data were revised for the quaternary carbons of both 1 and 3 with the help of HMBC spectra in respect to the spectral data previously reported in the literature. Compounds 1 and 3, two very potent anticancer agents, were isolated in high yields from the roots of the plant. The biological activities of the plants' constituents were reported in the literature as antimicrobial, cytotoxic and antimalarial are discussed in this article.

Abietane and nor-abitane diterpenoids from the roots of Salvia rhytidea.

BACKGROUND: The genus Salvia is a rich source of structurally diverse terpenoids. Different species of the Salvia have been used in folk medicine of Iran and therefore attracted the attention of researchers for exploring their chemical constituents. In a project directed at structurally interesting bioactive metabolites from Iranian Lamiaceae, we studied Salvia rhytidea. RESULTS: Fractionation of the petroleum ether extract of the root of S. rhytidea led to the isolation of a new 20-nor-abietane diterpenoid (1), together with seven known compounds, comprising five abietane diterpenoids (2-6), and two rearranged abietanes (7, 8). Their structures were established by a combination of 1D and 2D NMR. CONCLUSIONS: Our results showed that the root of S. rhytidea could be considered as a new and rich source of different types of abietane and rearranged abietane diterpenoids.

Total syntheses of the coumarin-containing natural products pimpinellin and fraxetin using Au(I)-catalyzed intramolecular hydroarylation (IMHA) chemistry.

The title natural products (1 and 2, respectively) have been synthesized by Au(I)-catalyzed intramolecular hydroarylation (IMHA) of the relevant aryl propiolate esters (e.g., 13), which were themselves formed by reaction of the corresponding phenols with either 3-(trimethylsilyl)propiolic acid or propiolic acid and N-(3-dimethylaminopropyl)-N'-ethylcarbodiimide hydrochloride or dicyclohexylcarbodiimide. (±)-Purpurasol (3) was readily derived from fraxetin (2) by established procedures.

Synthesis of cyano-2,3-dihydropyrrolo[1,2-f]phenanthridine derivatives via a domino-Knoevenagel-cyclization.

In a new multicomponent reaction phenanthridine reacts with isocyanides and malonitrile in the presence of benzaldehyde derivatives to produce 2-aryl-3-(alkyl- or arylimino)-2,3-dihydropyrrolo[1,2-f]phenanthridine-1,1(12b H)-dicarbonitrile in a simple, mild, and efficient protocol in excellent yields.

Synthesis of 5-aryl-1,3-dimethyl-6-(alkyl- or aryl-amino) furo [2,3-d]pyrimidine derivatives by reaction between isocyanides and pyridinecarbaldehydes in the presence of 1,3-dimethylbarbituric acid.

5-Aryl-6-(alkyl- or aryl-amino)-1,3-dimethylfuro [2,3-d]pyrimidine derivatives were obtained by in situ reaction alkyl or aryl isocyanides and pyridinecarbaldehyde derivatives in the presence of 1,3-dimethylbarbituric acid in dichloromethane without any prior activation or modifications.

Efficient synthesis of stable phosphonate ylides and phosphonate esters: reaction between activated acetylenes and triphenylphosphite in the presence of sulfonamide and heterocyclic NH-acids.

An efficient synthesis of stable phosphonate ylides and phosphonate esters is described via a one-pot reaction between activated acetylenes and triphenylphosphite in the presence of sulfonamides and heterocyclic NH-acids. Single X-ray diffraction analysis and NMR studies were used in characterizing the ylides and phosphonate ester products. Dynamic NMR studies performed on a phosphonate ylide allowed the calculation of the free energy barrier for the inter-conversion between the geometrical isomers (E) and (Z).