Ultrasound-Promoted Synthesis of Biologically Active α-Hydroxyphosphonates/ Hydroxyphosphinates Using 1,4-Dimethylpiperazine as a Catalyst

<div><p> </p><p>A series of new α-hydroxyphosphonates/phosphinates was prepared using 1,4-dimethylpiperazine as a base catalyst under conventional as well as ultrasonic irradiation conditions by the reaction of 5-bromoindole-3-carboxaldehyde/2-nitrocinnamaldehyde with various phosphonates/phosphinates. The high yields of α-hydroxyphosphonates/hydroxyphosphinates were obtained in less reaction time under the ultrasonic irradiation method as compared with the conventional method. The synthesized compounds were screened for their in vitro and in vivo antioxidant activities, and the bio-screening data revealed that all the tested compounds exhibited good antioxidant activities. The bio-screening data revealed that compound <b>8e</b> exhibited potent antioxidant activity in both in vitro and in vivo studies while the other compounds exhibited good antioxidant activity.</p><p>[Supplementary materials are available for this article. Go to the publisher's online edition of <i>Phosphorus, Sulfur, and Silicon and the Related Elements</i> for the following free supplemental files: Additional text, tables and figures.]</p>