This study was undertaken on the basis of several reports in the literature that pancreatic beta cells are capable of replication/regeneration and also being afforded protection against damage induced by streptozotocin. Nicotinamide was reported to give protection against streptozotocin-induced damage in rats. In the present study, two thiazolidine-4-ones with nicotinamide substitution were administered to Swiss albino mice with streptozotocin diabetes for 15 days. Concurrently, one group received nicotinic acid. Both the test compounds reversed the hyperglycaemia diabetic mice. Damage to pancreatic islets was also reduced in these groups compared to diabetic control and nicotinic acid treated groups. Since these compounds have been earlier found have antioxidant activity, one of the possible mechanisms of action could be by reducing oxidative stress in pancreas. Further, possibly by releasing nicotinamide in vivo, the molecules could have contributed to the NAD pool in pancreas and afforded protection. It is concluded that the test compounds have potential to be developed for multiple beneficial action in conditions like metabolic syndrome.