Terpenes Terpenes U 0200 First Synthesis of Dialkyl Phosphonate Derivatives of Sesquiterpene α-Methylene-γ-lactone. -[stereoselective synthesis and structure of two phosphorus-containing derivatives (III) of guaianolide arglabin (I)]. -(JALMAHANBETOVA, R. I.; RAKHIMOVA, B. B.; RALDUGIN*, V. A.; BAGRYANSKAYA, I. Y.; GATILOV, Y. V.; SHAKIROV, M. M.; KULYJASOV, A. T.; ADEKENOV, S. M.; TOLSTIKOV, G. A.; Russ. Chem. Bull. 52 (2003) 3, 748-751; Vorozhtsov Inst. Org. Chem., Sib. Branch Russ. Acad. Sci., Novosibirsk 630090, Russia; Eng.) -Staver 41-192
A new germacranolide, ajanolide A, was isolated from aerial parts of Ajania fruticulosa by means of extraction with CHCI 3 and adsorption chromatography. This compound was identified as (l(lO)E,3S,4Z,6R,7S,11R)-3-acetoxygermacra-l(lO),4~ (( I S,7S, 1 OR, 13 R)-%acetoxy-4,8,13-trimethyl-11 -oxabicycIo[8.3.0]trideca-4(E),8(~-dien -12-one) by X-ray diffraction analysis. 2D IH--tH (COSY) and t3C--1H (COSY) NMR spectroscopy was used for assigning the tH and 13C NMR signals in the spectra of ajanolide A.
The reaction of sesquiterpene lactone achillin with chlorine in methanol afforded four products, via.. two monochlorides and two dichlorides. One of these monochlorides is an intermediate in the formation of both dichlorides. The structures of the reaction products were established by two-dimensional N M R spectroscopy The structure of one of the products was also established by X-ray diffraction analysis.
Other natural productsOther natural products U 0800Chlorination of Tectochrysin and Pinostrobin in Methanol. -The chlorination of natural flavonoids (I) and (III) gives rise to their 6,8-dichloro derivatives. Under the reaction conditions, dichloropinostrobin (V) is transformed further into a tetrachloromethoxy derivative (VI). -(KULMAGAMBETOVA, E. A.; SEITEMBETOVA, A. G.; KULYJASOV, A. T.; RALDUGIN*, V. A.; GATILOV, Y. V.; SHAKIROV, M. M.; ADEKENOV, S. M.; TOLSTIKOV, G. A.; Russ. Chem. Bull. 52 (2003) 3, 752-754; Vorozhtsov Inst. Org. Chem., Sib. Branch Russ. Acad. Sci., Novosibirsk 630090, Russia; Eng.) -Staver 41-219
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