Concomitant Pseudopolymorphs of 10-Deacetyl Baccatin III

Abstract

Abstract. Three new solvates [mono-dimethyl sulfoxide (mono-DMSO), mono-dimethyl acetamide (mono-DMA) and mono-dimethyl formamide (mono-DMF)] of 10-Deacetyl baccatin III, were generated by slow evaporation in DMSO, DMF, and DMSO/DMA (1:1) solvent systems respectively. Two concomitant forms mono-DMSO(a new form) and di-DMSO (a known form) were obtained in the DMSO solvent system. Yet two other concomitant forms mono-DMA (a new form) and di-DMSO (a known form) were obtained in DMSO/DMA (1:1) solvent system. A fourth solvate mono-DMF (a new form) was crystallized in unimolar ratio using DMF as a solvent. These solvates were characterized using powder X-ray diffraction, differential scanning calorimeter, thermogravimetric analysis (TGA), and spectroscopic [ 13 C solid-state nuclear magnetic spectroscopy, solution 1 H NMR, and Fourier transform infrared] techniques. The interactions between host and guest molecules were elucitated by single-crystal X-ray diffraction data. In all the cases, guest molecules are connected to the host molecules by O-H···O hydrogen bonds. A remarkable difference in the desolvation onset temperatures of di-and mono-DMSO solvates was observed which was also featured by a corresponding weight loss during TGA analysis.

Omic analysis of the endangered Taxaceae species Pseudotaxus chienii revealed the differences in taxol biosynthesis pathway between Pseudotaxus and Taxus yunnanensis trees

“…Here, one unigene encoding DBAT and two unigenes encoding BAPT were identified, and they predominantly expressed in P. chienii . In pharmaceuticals industry, baccatin III and 10-DAB are key starting material of pacitaxel [ 46 ]. Our data showed that baccatin III and 10-DAB highly accumulated in P. chienii , suggesting a great economic value of P. chienii extracts.…”