Synthesis and biological evaluation of some new N⁴-substituted isatin-3-thiosemicarbazones

Figures & data

Scheme 1..  Synthesis of title compounds.

Figure 1.  The proposed fragmentation pattern of the compound 2a.

Table I..  Brine shrimp bioassay for compounds 2a-l.

Compounds	LD50 (M)
2a	3.10 × 10^− 5
2b	1.60 × 10^− 5
2c	1.21 × 10^− 4
2d	1.80 × 10^− 5
2e	1.36 × 10^− 4
2f	2.20 × 10^− 5
2g	1.17 × 10^− 4
2h	2.00 × 10^− 5
2i	2.10 × 10^− 5
2j	2.00 × 10^− 5
2k	2.10 × 10^− 5
2l	1.10 × 10^− 5
2m [19,20]	>3.38 × 10^− 4

Table II..  Percent growth inhibition of Lemna aequinocitalis by compounds 2a-l at different concentrations.^*

Compound	500 (μg/mL) (% G.I.^†)	50 (μg/mL) (% G.I.^†)	5 (μg/mL) (% G.I.^†)
2a	40	25	00
2b	10	5	00
2c	10	05	00
2d	15	10	05
2e	15	10	00
2f	10	05	00
2g	15	10	05
2h	10	05	00
2i	10	05	00
2j	25	15	10
2k	30	25	15
2l	20	15	10
2m [19]	10	05	00

^* The reference compound paraquat shows 100% growth inhibition at a concentration of 0.015 μg/mL

^† G.I.: growth inhibition.

Table III..  Inhibition of Jack bean urease by compounds 2a-l.

Compounds	Percentage (%) of inhibition at 100 μM	IC50 ± SEM (μM)
2a	84.9	20.6 ± 0.5
2b	57.3	50.6 ± 2.2
2c	40.7
2d	49.6
2e	63.1	33.1 ± 0.35
2f	78.2	20.6 ± 0.07
2g	44.6
2h	71.9	47.6 ± 0.4
2i	66.6	47.9 ± 0.96
2j	92.0	33.1 ± 0.35
2k	38.8
2l	79.6	28.6 ± 1.8
2m [19,20^*]	NA
Thiourea^†		21.0 ± 0.01

^* Screened against human urease; NA: no inhibitory activity

^† Standard inhibitor of urease enzyme.

H Pervez, MS Iqbal, MY Tahir, MI Choudhary, and KM Khan. (2007). Synthesis of some N4-substituted isatin-3-thiosemicarbazones. Nat Prod Res 21:1178–1186.

 PubMed Web of Science ®Google Scholar

H Pervez, MS Iqbal, MY Tahir, FH Nasim, MI Choudhary, and KM Khan. (2007). In vitro cytotoxic, antibacterial, antifungal and urease inhibitory activities of some N4-substituted isatin-3-thiosemicarbazones. J Enz Inhib Med Chem iFirst:1–7. 10.1080/14756360701746179

 Google Scholar