Synthesis of spongian diterpenes: (−)-spongian-16-oxo-17-al and (−)-acetyldendrillol-1
作者:Manuel Arnó、Miguel A González、M.Luisa Marı́n、Ramón J Zaragozá
DOI:10.1016/s0040-4039(00)02339-x
日期:2001.2
An efficient diastereoselective synthesis of the spongian diterpenes (−)-spongian-16-oxo-17-al (1) and (−)-acetyldendrillol-1 (13) is described starting from (+)-podocarp-8(14)-13-one (6) via the ester-dialdehyde 11 as key intermediate. The absolute configuration at C-17 in synthetic compound 13 has conclusively been proved by NOE experiments.
In this article, a novel methodology for the study of complex reaction mechanisms is explored, and applied to the kinetic analysis of the hydrolysis reactions of ciclohexanecarbonitriles. The kinetic data were first analyzed with the help of classic linear techniques. Subsequently, the determination of the rate constants by a non-linear, least-squares (LS) fitting method, followed by a novel eigenvalue-eigenvector analysis of the sensitivity coefficients, permitted us to obtain the maximum possible information from the kinetic data. The non-linear, LS-fitting method, carried out by means of a new version of OPKINE program, allowed the calculation of all the rate constants of the mechanism; in addition, the sensitivity analysis permitted us to establish the uniqueness and reliability of calculated rate coefficients. Finally, the results of the sensitivity analysis were tested by means of a simulation procedure, and the results compared to those obtained from classic linear methods. (C) 1999 John Wiley G Sons, Inc. Int I Chem Kinet 31: 611-626, 1999.
Synthesis of C-17-Functionalized Spongiane Diterpenes: Diastereoselective Synthesis of (−)-Spongian-16-oxo-17-al, (−)-Acetyldendrillol-1, and (−)-Aplyroseol-14
作者:Manuel Arnó、Miguel A. González、Ramón J. Zaragozá
DOI:10.1021/jo026536f
日期:2003.2.1
The diastereoselective synthesis of spongiane diterpenes (-)-spongian-16-oxo-17-al 2, (-)-acetyldendrillol-1 15, and (-)-aplyroseol-14 16 has been completed efficiently via the common intermediate 14. Compound 14 was prepared in five synthetic steps from (+)-podocarp-8(14)-en-13-one 13, easily available from commercial (-)-abietic acid. The key steps in the syntheses were a regioselective reduction