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Studies on Covalent Adducts of Dehydrouric Acid

N. Modrić ; Laboratory of Organic Chemistry, Faculty of Science, University of Zagreb, Strossmayerov trg 14, Zagreb, Croatia
A. Palković ; Laboratory of Organic Chemistry, Faculty of Science, University of Zagreb, Strossmayerov trg 14, Zagreb, Croatia
I. Perina ; Laboratory of Organic Chemistry, Faculty of Science, University of Zagreb, Strossmayerov trg 14, Zagreb, Croatia
M. Poje ; Laboratory of Organic Chemistry, Faculty of Science, University of Zagreb, Strossmayerov trg 14, Zagreb, Croatia
I. Vicković ; Laboratory of General and Inorganic Chemistry, Faculty of Science, University of Zagreb, PO Box 153, Zagreb, Croatia

Puni tekst: engleski, pdf (32 MB) str. 347-360 preuzimanja: 124* citiraj
APA 6th Edition
Modrić, N., Palković, A., Perina, I., Poje, M. i Vicković, I. (1994). Studies on Covalent Adducts of Dehydrouric Acid. Croatica Chemica Acta, 67 (3), 347-360. Preuzeto s https://hrcak.srce.hr/136878
MLA 8th Edition
Modrić, N., et al. "Studies on Covalent Adducts of Dehydrouric Acid." Croatica Chemica Acta, vol. 67, br. 3, 1994, str. 347-360. https://hrcak.srce.hr/136878. Citirano 01.03.2021.
Chicago 17th Edition
Modrić, N., A. Palković, I. Perina, M. Poje i I. Vicković. "Studies on Covalent Adducts of Dehydrouric Acid." Croatica Chemica Acta 67, br. 3 (1994): 347-360. https://hrcak.srce.hr/136878
Harvard
Modrić, N., et al. (1994). 'Studies on Covalent Adducts of Dehydrouric Acid', Croatica Chemica Acta, 67(3), str. 347-360. Preuzeto s: https://hrcak.srce.hr/136878 (Datum pristupa: 01.03.2021.)
Vancouver
Modrić N, Palković A, Perina I, Poje M, Vicković I. Studies on Covalent Adducts of Dehydrouric Acid. Croatica Chemica Acta [Internet]. 1994 [pristupljeno 01.03.2021.];67(3):347-360. Dostupno na: https://hrcak.srce.hr/136878
IEEE
N. Modrić, A. Palković, I. Perina, M. Poje i I. Vicković, "Studies on Covalent Adducts of Dehydrouric Acid", Croatica Chemica Acta, vol.67, br. 3, str. 347-360, 1994. [Online]. Dostupno na: https://hrcak.srce.hr/136878. [Citirano: 01.03.2021.]

Sažetak
The structure of 5-chloro and 5-alkoxy-5,7-dihydro-3//-purine-2,4,6-trio- nes (6 and 7-9) has been corroborated by their spectral properties and X-ray crystallography. The stereochemical model (fì)-10 of the key uricolytic intermediate was prepared using menthol as chiral auxiliary. In acidic solutions, depending on the N-substitution, the ring cleavage occurred either at the 4,9-bond 6b -» 13 (R1 = Me) or at the 3,4-bond 6c -» 14 (R1 = H).
Opening of the 1,6-bond is the dominant process under alkaline conditions. Decarboxylative rearrangement into 1,3-dimethylallantoin (15) was specific for N(7)-unsubstituted derivatives. Evidence for intermediacy of the bicyclol tautomeric form was supplied by isolation of l-menthoxy-2,4-dimethyl-3,7-di- oxo-2,4,6,8-tetraazabicyclo[3.3.0]octane (16); fragmentation of 10 into 5- menthoxy-imidazolidin-2,4-dione (17) also takes place under forcing conditions. Conversely, no allantoin rearrangement was encountered in the R7*H cases; 7d underwent the pyrimidine ring fragmentation to give 5-methoxy-l- methyl-4-methylimino-imidazolidine-2-one (18) or 5-carboxamido-5-methoxy- l-methyl-4-methylimino-imidazolidine-2-one (19). A possible mechanism for these ring transformation reactions is discussed.

Hrčak ID: 136878

URI
https://hrcak.srce.hr/136878

Posjeta: 224 *