## Abstract Diiodothyronines 3,5‐diiodothyronine (3,5‐T2), 3′,5′‐diiodothyronine (3′,5′‐T2), and 3,3′‐diiodothyronine (3,3′‐T2) are important metabolites of 3,5,3′‐triiodothyronine (T3) and 3,3′,5′‐triiodothyronine (rT3; reverse T3). In this paper, a novel and rapid method for identifying and quant
Fragmentation study of simvastatin and lovastatin using electrospray ionization tandem mass spectrometry
✍ Scribed by Hong Wang; Yunhui Wu; Zhongxi Zhao
- Publisher
- John Wiley and Sons
- Year
- 2001
- Tongue
- English
- Weight
- 302 KB
- Volume
- 36
- Category
- Article
- ISSN
- 1076-5174
- DOI
- 10.1002/jms.104
No coin nor oath required. For personal study only.
✦ Synopsis
The fragmentation mechanism of simvastatin and lovastatin was investigated using both triple quadrupole and ion trap mass spectrometers. The elimination of the ester side-chain followed by dehydration and dissociation of the lactone moiety were observed as the main fragmentation pathways for both compounds. Another major fragmentation process was a C==C double-bond facilitated rearrangement. Our tandem mass spectrometric (MS/MS) data suggested that the beta-hydroxy group was involved in the fragmentation by interacting with the carboxyl group generated from the ring opening of the lactone. As a result, a facile neutral loss of 60 Da (CH(3)COOH or a combination of CH(2)==C==O and H(2)O) was detected. MS/MS studies of the structural analogs also provided evidence that the dehydration of the beta-hydroxy lactone generated preferentially the beta,gamma-unsaturated lactones.
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