I<sub>2</sub> mediated synthesis of 5-substituted-3-methyl/benzyl-1,3,4-oxadiazol-2(3H)-ones via sequential condensation/oxidative cyclization and rearrangement
A simple and efficient iodine-assisted protocol for the synthesis of 5-substituted-3-methyl/benzyl-1,3,4-oxadiazol-2(3H)-ones has been developed. The reaction involves a sequential condensation followed by tandem oxidative cyclization and rearrangement of readily available methyl/benzyl carbazates and aldehydes as starting substrates. The presence of iodine and base promotes intramolecular C–O bond
The invention provides a pyrimidodiazepinone derivative represented by the general formula (I)
[wherein n represents 1 or 2, Z represents a hydrogen atom or the like, R1 and R2 may be the same or different, and each represents a hydrogen atom or the like, A represents a bond, (CH2)m (wherein m represents an integer of 1 to 4), optionally substituted phenylene, optionally substituted pyridinediyl, or C═O, R3 represents a hydrogen atom, optionally substituted lower alkyl, or the like, and R4 represents a hydrogen atom or the like], or a pharmaceutically acceptable salt thereof or the like.