Synthesis of Isoxazolopyridines and Spirooxindoles under Ultrasonic Irradiation and Evaluation of Their Antioxidant Activity

Table 2

Synthesis of isoxazolopyridine derivatives in the presence of catalytic amount of (±)-CSA.

Product	Ar	Time (min)	Yield
4a	Phenyl	120	71
4b	4-Cyanophenyl	120	76
4c	4-Benzyloxyphenyl	120	78
4d	2,4-Difluorophenyl	120	73
4e	Thiophen-2-yl	120	78
5f	3-Phenoxyphenyl	120	72
5g	Furan-2-yl	120	80
5h	Pyridine-2-yl	120	73

yield.