Hempel A, Camerman N, Camerman A
Department of Biochemistry, University of Toronto, Ontario, Canada.
Cancer Biochem Biophys. 1988 Jul;10(1):25-30.
The structure of the non-classical quinazoline antifolate trimetrexate (TMQ) has been determined in two crystal forms, TMQ acetate monohydrate, and hydrated TMQ free base. Trimetrexate has an extended conformation in both structures, and the quinazoline and phenyl rings are mutually perpendicular. Protonation occurs at N1 in the acetate salt. The TMQ conformation is similar to corresponding parts of quinespar, the only other quinazoline antifolate structurally determined, and the hydrated strontium salt of methotrexate.
非经典喹唑啉抗叶酸药三甲曲沙（TMQ）的结构已通过两种晶体形式确定，即一水合三甲曲沙乙酸盐和水合三甲曲沙游离碱。在这两种结构中，三甲曲沙均具有伸展构象，喹唑啉环和苯环相互垂直。在乙酸盐中，质子化发生在N1处。TMQ的构象与喹诺司帕（唯一一种结构已确定的其他喹唑啉抗叶酸药）以及甲氨蝶呤的水合锶盐的相应部分相似。
