Table 3.

Physical data of the compounds 7a-o

Entry	R	M. P. (°C)	Yield %
7a		260–262	85
7b		222–225	83
7c		285–288	80
7d		275–277	88
7e		248–250	78
7f		256–258	90
7g		288–290	89
7h		280–284	85
7i		290–293	70
7j		> 300	78
7k		288–290	84
7l		> 300	89
7m		244–246	85
7n		223–225	85
7o		260–263	85