Fragmentation pattern in mass spectra of some isocoumarins (la-e), dihydroisocoumarins (1a-e) and related compounds (3-4a-e) are described with the help of ElMS. The molecular formulae are further confirmed by HREIMS peak matching of molecular ion peaks exhibited in EIMS.
M HUSSAIN ,MUHAMMAD T HUSSIAN ,NASIM H RAMA ,
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