1H-NMR and 13C-NMR assignments of 12-oleanene-3,11-dione (compound 1) were completely described for the first time through conventional 1D NMR and 2D shift-correlated NMR experiments using 1H-1HCOSY, HMQC, HMBC techniques. Based on its NMR data, the assignments of 28-hydroxyolean-12-ene-3,11-dione (compound 2) were partially revised.
The title compound,(1α,6β,11β,14α)-1,7:6,20-diepoxy-6,11-dihydroxy-6,7-seco-ent-kaur-16-ene-7,15-dione-14-acetate (macrocalyxin J),is a diterpenoid which was isolated from the leaves of Rabdosia macrocalyx and characterized by single-crystal X-ray diffraction. It cry-stallizes in orthorhombic,space group P212121 with a=9.3608(8),b=14.9787(12),c=15.5750(13) ,Z=4,V=2183.8(3) 3,C22H30O9,Mr=438.46,Dc=1.334 g/m3,μ(MoKα)=0.103 mm1,F(000)=936,the final R=0.0532 and wR=0.1262 for 2252 observed reflections (I > 2σ(I)). In the molecule,three six-membered rings adopt chair,boat and slightly distorted boat conformations,respectively,while both five-membered rings have approximate envelope conformations.
对活性天然产物(+)-7-deoxyn imb id iol非对映异构体的外消旋体cis-(±)-7-deoxyn imb id iol进行了合成和衍生,共得到了8个新型三环二萜化合物;对合成的新化合物进行了抗肿瘤活性的实验研究,其中化合物5d对人体乳腺癌瘤株MCF7表现出了较强的抑制作用(IC50=7.49μg/mL),可能作为新型抗肿瘤药物先导化合物.
On the basis of the investigation on natural product antitumor agents,a new diterpenoid named macrocalyxin J was isolated from the leaves of Rabdosia macrocalyx（Dunn） Hara by silica gel column chromatography.Based on IR,MS,1H NMR,13C NMR and 2D NMR spectroscopies,the structure of macrocalyxin J was determined as（1α,6β,11β,14α）-1,7∶6,20-diepoxy-6,11-dihydroxy-6,7-seco-ent-kaur-16-ene-7,15-dione-14-acetate.The antitumor activity of the compound was assayed by MTT method.Macrocalyxin J was shown to have a potency in vitro against the cultures of Hela cells.
