Amino band of 2-amino-5-(2,4-difluorophenyl)-6H-pyrido[1,2-b]pyridazin-6-one was actually reacted with (2-fluorophenyl)isocyanate, with 2,4-difluorobenzoyl chloride to offer 2-[N 2 -(2-fluorophenyl)ureido] and (2,4-difluorobenzoyl)amino derivatives, respectively (07USA372).
126.96.36.199 N-Linked Substituents
Amino organizations connected to the chromone band system would not be anticipated to has identical residential properties since only one ring is actually completely aromatic. Their education of aromaticity with the pyran-4-one band is leaner than compared to benzene, since 2,3-double bond does take part in a few addition reactions, since has-been pointed out. The fragrant koko app logowanie dynamics in the pyran-4-one band are sustained by the capacity from the 3-amino team becoming diazotized and converted into the hydroxyl cluster a€?78JCR(S)47a€‰ . There is certainly, in contrast, doubt regarding the nature of 2-aminochromone and its own derivatives; they are tautomeric and on hydrolysis provide coumarins. This implies that they exists at the very least to some degree when you look at the imino type ( 524 ) but spectroscopic and chemical proof, while not absolute, highly offer the NH2 kind for diacetyl product ( 526 ) prepared from 2-amino-3-chlorochromone ( 518 ) or their tautomer a€?74JCS(P1)2570a€‰ . The reduced nucleophilicity associated with 2-amino team is evident various other reactions and is in line with the are (like 4-aminocouide a€?81JHC697a€‰ .
A nitrochromone possess three conveniently reducible functions and, for its decrease, circumstances and reagents which have minimal effect on the carbonyl or perhaps the 2,3-double bond must certanly be plumped for.