Journal of the Chemical Society. Perkin transactions II p. 1777 - 1780 (1984)
Update date:2022-08-04
Topics:
Schuchmann, Man Nien
Al-Sheikhly, Mohamed
Sonntag, Clemens von
Garner, Anthony
Scholes, George
Isopyrimidines are formed as a result of the oxidation of the 6-yl radicals derived by .OH attack on pyrimidines and dihydropyrimidines.The kinetics of the rearrangement of the isopyrimidines into the corresponding pyrimidines has been followed by pulse radiolysis.The rearrangement of isouracil into uracil is proton-catalysed (k 1.8E7 l mol-1 s-1).Around pH 7 a spontaneous reaction, k 3000 s-1, is observed.On increasing the pH the isouracil deprotonates at N(3) (pKa ca. 9.4).The spontaneous rearrangement of the isouracil anion is considerably slower (k -1).At pH > 10.5 an OH(1-)-catalysed reaction sets in (k 4.9E5 l mol-1 s-1) which involves a second deprotonation, at C(5).Similar results have been obtained for the rearrangement of 5-hydroxyisouracil into isobarbituric acid.On blocking the N(3) position as in 3-methylisouracil, the OH(1-)-induced rearrangement sets in at a much lower pH (pH-1 s-1) than that observed in the other two systems.
View MoreQINGDAO TAOSIGN INTERNATIONAL TRADE CO.,LIMITED
Contact:+86-0532-82683616
Address:RM1402, Doublestar Seacoase 7#, No. 5 Guizhou Road, Qingdao, Shandong, China
Contact:+86-(0)21-3770 9035
Address:Room 301, Building 2, Meijiabang Road 1508, Shanghai China
Guangzhou Reachin Chemical Co., Ltd
Contact:+86-20-37087379 ext.604
Address:A122C-1, Tianyuan Plaza, 401 Tianyuan Rd., Tianhe, Guangzhou, China
Jinhua City Mingzhu Pharmaceutical Co.,Ltd.
Contact:15857995878 0579-82207761
Address:No.169 Shenze Road, New Area,Jinpan Development Zone, Jinhua
WENZHOU M&C FOREIGN TRADE CO.,LTD.
Contact:+86-577-88862917
Address:No.8 Liming West Road,Wenzhou,zhejiang,China
Doi:10.1016/j.bmcl.2007.06.026
(2007)Doi:10.1021/jo00172a061
(1983)Doi:10.1021/ja00363a033
(1983)Doi:10.1002/anie.201913126
(2020)Doi:10.1002/hlca.200590231
(2005)Doi:10.1016/j.tetlet.2005.11.046
(2006)
