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Updated: Mar 5, 2026

Construction and Systematical Symmetric Studies of a Series of Supramolecular Clusters with Binary or Ternary Ammonium Triphenylacetates
Published on: February 15, 2016
Crystal Structures and Vapor-Induced Crystalline Transformation of 7-Ethyl-10-Hydroxycamptothecin Pseudopolymorphs
Lan Fang1, Lei Wang1, Changlin Yao1
1State Key Laboratory of Crystal Materials, Shandong University, No. 27 Shanda South Road, Jinan 250100, China.
Abstract:
Solvent-induced 3 frameworks (the monohydrate, methanol solvate, and dimethyl formamide [DMF] solvate) of an anticancer drug, 7-ethyl-10-hydroxycamptothecin (SN38), were constructed. The crystal structures of the 3 pseudopolymorphs were characterized by single-crystal X-ray diffraction technique for the first time. Crystal structure analysis of all these polymorphs revealed that the monohydrate showed 3D frameworks linked by hydrogen bonds. In the methanol solvate, the 1D molecular chains were linked by the methanol molecules through intermolecular hydrogen bonds to form a 2D sheet. The DMF solvate exhibits the 1D hydrogen bonding-linked chains along b-axis. Vapor-induced transformation has been investigated for the monohydrate, the methanol solvate, and the DMF solvate. The conversion relationships among the 3 solid frameworks are illustrated. Insights regarding transformation mechanisms have been established from consideration of the crystal structures.
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