Protium/deuterium exchange in oxazinediones

✍ Scribed by Stephen S. Washburne; Hosull Lee

• Book ID: 104245695
• Publisher: Elsevier Science
• Year: 1978
• Tongue: French
• Weight: 120 KB
• Volume: 19
• Category: Article
• ISSN: 0040-4039
• DOI: 10.1016/s0040-4039(01)94642-8

✦ Synopsis

Recent interest in the 1,3-oxazine-2,6-dione ring system', an isosteric equivalent of uracil and thymine, as an antimetabolite and anti-leukemic agent2 , prompts us to report on the relative exchangeability of the protons of 4-methyl-1,3-oxazine-2,6-dione, ,& in acidic media, which may have bearing on the mode of action of this compound and its alkylated derivatives. In the oresence of acid, a priori, one would predict rapid exchange at the amidic N-H site, somewhat slower exchange at the vinylogous enolic methyl site, and slow, in any, exchange at the olefinic C-H site. Surprisingly, when a was treated with 6.1N DC1 in D20, in a reaction monitored by 'H-nmr, the olefinic resonance disappeared faster than did the methyl resonance.