西地那非衍生物的电喷雾离子阱质谱研究

采用电喷雾离子阱质谱法对4种西地那非衍生物进行了质谱研究,获得了它们的结构碎片信息,通过比较它们的异同对其质谱裂解途径进行解析,发现它们的（+）ESI-MS2质谱生成磺酰基S-C键和S-N键断裂、亚甲氧基C-O键断裂以及磺酰基重排后C-S键断裂的碎片,基峰为亚甲氧基C-O键断裂产生,其（+）ESI-MS3质谱生成脱NH3、脱CO、脱NH=C=O以及异环开裂碎片,这些特征可用于阐明西地那非衍生物及其结构类似物的结构。

Studies on the Electrospray Ion Trap Mass Spectra of Sildenafil Derivatives

To investigate the characteristics of mass spectra of four sildenafil derivatives, their fragments were analyzed using electrospray ion trap mass spectrometry in a multi-stage MS full scan mode performed on a Finnigan LCQ instrument. The mass spectrometry were operated in the positive mode. The mass spectra were obtained mainly by analyzing the fragments of the four compounds. The full scan MS2 spectra of each compound gave characteristic fragment ions formed through cleavage of the S-N, S-C, C-O bond between the pyrimidine ring and the aromatic ring, the cleavage of the C-S bond after the arrangement of sulfuryl group, respectively. The base peak of the MS2 spectra was formed though the C-O cleavage. The full scan MS3 spectra gave characteristic fragment ions obtained after elimination of carbon monoxide, ammonia, acidamide and undergoing the retro-Diels-Alder reaction in pryrazole-pyrimiding rings, respectively. These character-istics can be used for future structure elucidation in studies of analogues of sildenafil.