Table 4. Derivatives of Series 9 Synthesized with Various Aldehydes along with Obtained Results.

entry	producta	R	yield (%)	Rf value	melting point (°C)
1	9a	C6H5	91	0.45	219–220
2	9b	4-NO2-C6H4	94	0.69	233–235
3	9c	4-Me-C6H4	85	0.59	194–196
4	9d	4-OMe-C6H4	89	0.52	209–210
5	9e	2-OH-C6H4	83	0.64	221–222
6	9f	3-NO2-C6H4	85	0.60	229–230
7	9g	4-OH, 3-OCH3 C6H3	90	0.61	247–249
8	9h	C6H4-CH=CH	81	0.53	216–217
9	9i	2-pyridinyl	64	0.66	209–210
10	9j	2-furyl	92	0.72	189–191
11	9k	2-thiophenyl	90	0.68	192–193

^aProducts were characterized with standard and reliable spectral techniques.