A validated stability-indicating normal phase LC method for clopidogrel bisulfate and its impurities in bulk drug and pharmaceutical dosage form.

A novel stability-indicating normal phase liquid chromatographic (NP-LC) method was developed for the determination of purity of clopidogrel drug substance and drug products in bulk samples and pharmaceutical dosage forms in the presence of its impurities and degradation products. This method is capable of separating all the related substances of clopidogrel along with the chiral impurities. This method can be also be used for the estimation of assay of clopidogrel in drug substance as well as in drug product.

5-Meth-oxy-2,2-dimethyl-6-[(2E)-2-methyl-but-2-eno-yl]-10-phenyl-2H,8H-pyrano[2,3-f]chromen-8-one (calophyllolide).

The title compound, C(26)H(24)O(5), was isolated from calophyllum inophyllum seeds. In the mol-ecule, the phenyl and 2-methyl-but-2-enoyl groups are almost orthogonal to the chromene fragment [C-C-C-C torsion angles = 81.4 (3) and -90.