3β-Acetoxy-lup-20(29)-en-28-yl 1H-1,2,4-triazole-1-carboxylate
نویسندگان
چکیده
The title triterpene, C(35)H(53)N(3)O(4), is a C-28 carbamate derivative of 3β-acet-oxy-betulin prepared in a one-step reaction from the commercially available 1,1'-carbonyl-di(1,2,4-triazole) (CDT), crystallized from acetone/n-hexane. All rings are trans fused. The carbamate and acetate substituents are in axial and equatorial positions, respectively. A quantum chemical ab initio Roothaan Hartree-Fock calculation of the equilibrium geometry of the isolated mol-ecule gives values for bond lengths and valency angles in close agreement with experimental values. The calculation also reproduces the observed mol-ecular conformation, with puckering parameters that agree well with those determined from the crystallographic study.
منابع مشابه
The triterpenes 3β-lup-20(29)-en-3-ol and 3β-lup-20(29)-en-3-yl acetate and the carbohydrate 1,2,3,4,5,6-hexa-O-acetyl-dulcitol as photosynthesis light reactions inhibitors.
Three compounds were isolated from Maytenus acanthophylla Reissek (Celastraceae): the pentacyclic triterpenes lup-20(29)-en-3β-ol (lupeol, 1) and 3β-lup-20(29)-en-3-yl acetate (2) and the carbohydrate 1,2,3,4,5,6-hexa-O-acetyldulcitol (3); lupeol was also isolated from Xylosma flexuosa. The compounds' structures were elucidated by spectroscopic and spectrometric analysis. Compound 1 acts as an ...
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