Efficient synthesis and antimicrobial evaluation of some Mannich bases from 2-arylidine-1-thia-4-azaspiro[4.5]decan-3-ones

Table 4 Synthesis of the Mannich bases (6a-r)^a

Mannich product	Ar	R	Time (h)	Yield ^b (%)
6a	Ph	piperidin-1-yl	2.0	80
6b	Ph	morphilin-1-yl	3.0	76
6c	Ph	pyrrolidin-1-yl	2.5	79
6d	4-ClC₆H₄	piperidin-1-yl	1.5	91
6e	4-ClC₆H₄	morphilin-1-yl	2.5	88
6f	4-ClC₆H₄	pyrrolidin-1-yl	2.0	80
6g	4-BrC₆H₄	piperidin-1-yl	2.0	81
6h	4-BrC₆H₄	morphilin-1-yl	2.0	80
6i	4-BrC₆H₄	pyrrolidin-1-yl	3.0	80
6j	4-O₂NC₆H₄	piperidin-1-yl	3.0	76
6k	4-O₂NC₆H₄	morphilin-1-yl	4.0	71
6l	4-O₂NC₆H₄	pyrrolidin-1-yl	3.5	73
6m	4-MeOC₆H₄	piperidin-1-yl	1.5	89
6n	4-MeOC₆H₄	morphilin-1-yl	2.5	81
6o	4-MeOC₆H₄	pyrrolidin-1-yl	2.0	83
6p	4-pyridyl	piperidin-1-yl	2.0	89
6q	4-pyridyl	morphilin-1-yl	3.0	79
6r	4-pyridyl	pyrrolidin-1-yl	2.0	82

^a Reaction conditions: 2-arylidine-1-thia-4-azaspiro[4.5]decan-3-ones (5a-f) (10 mmol), formaldehyde (15 mmol), and secondary amine (15 mmol) in 10 mL absolute ethanol at room temperature.
^b Isolated yields.

ISSN: 2661-801X