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Synthesis of 4H‐3,3a‐dihydrothiazolo[4,3‐ b ]quinazolines
Author(s) -
Adegoke Emmanuel A.,
Alo Babajide I.,
Familoni Oluwole B.
Publication year - 1987
Publication title -
journal of heterocyclic chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.321
H-Index - 59
eISSN - 1943-5193
pISSN - 0022-152X
DOI - 10.1002/jhet.5570240122
Subject(s) - chemistry , iminium , medicinal chemistry , ion , phosphorus , organic chemistry , stereochemistry
Regiospecific synthesis of 4 H ‐3,3a‐dihydrothiazolo[4,3‐ b ]quinazolines and 7‐methyl‐4 H ‐3,3a‐dihydrothiazolo[4,3‐ b ]quinazolines IVa and IVb is described. The N ‐substituted thiazolidinecarboxylic acids Ia and Ib were converted to the corresponding acid chlorides, IIa and IIb but neither reacted with silver trifluoromethanesulphonate. The carboxylic acids Ic and Id were however, decarboxylated to the corresponding iminium ions using phosphorus oxychloride and these afforded the nitroamines IIIa and IIIb. Reductive cyclisation led to the quinazolines IVa and IVb.