4.2 Lawesson reagent and their derivatives
Lawesson reagent (LR) is a common and readily available sulfur ion agent that can serve as a hydrogen sulfide releaser (H2S releaser). The molecule of Lawson reagent contains a quaternary ring with alternating sulfur and phosphorus atoms. Under high temperature conditions, the sulfur/phosphorus quaternary ring opens to form two unstable dithiophosphines (R-PS2), which decompose and release H2S[51, 52]. Compared to sulfide salts, LR releases hydrogen sulfide more slowly[52]. However, the detailed release molecular dynamics of LR are still unclear and lack water solubility, so it has not been widely used as a hydrogen sulfide donor. morpholin-4-ium 4 methoxyphenyl (morpholino) phosphinodithioate (GYY4137) is a new water-soluble hydrogen sulfide donor synthesized based on LR reagent, which can slowly release hydrogen sulfide. Some studies have found that GYY417 has the function of dilating blood vessels to resist hypertension[53]. Not only that, it can also exert myocardial protection and prevent myocardial ischemia and reperfusion injury by inhibiting inflammation, reducing cell apoptosis, and reducing ROS production[54, 55]. In addition to its myocardial protective effect, some scholars have found that in ischemia-reperfusion injury, GYY4137 increases antioxidant activity by activating the Nrf2 signaling pathway, which can effectively alleviate renal injury[56]. This protective effect has also been reported in testicular torsion and intestinal injury[57, 58].