Organotin hydroxides Triphenyltin hydroxide

There is also no conclusive evidence that inorganic tin compounds have carcinogenic properties. However, there are data which indicate that organotin compounds (bis(tributyltin)oxide and triphenyltin hydroxide) may be tumorigenic at low levels of tin. Bis(tributyltin)oxide (2.5 mg/kg/day) and triphenyl tin hydroxide (0.3-6.2 mg/kg/day) were associated with pituitary adenomas in rats of both sexes with exposures of 104-106 weeks. When triphenyltin hydroxide was administered, the pituitary adenomas were present only in the females and contributed to decreased longevity. 

Dermal/Ocular Effects. Skin and eye irritations and dermatitis, but not sensitization, have been reported in humans and animals after dermal exposure of acute and intermediate-duration to both inorganic tin and organotin compounds. Mice also experienced a dermatological reaction to triphenyltin hydroxide after oral exposure over a period of 80 weeks. There is a reasonable probability of some skin, eye, and other mucous membrane contact with compounds at hazardous waste sites and the likelihood of irritation and other effects occurring. 

This active substance, appearing as white, odourless crystals, was developed by Van der Kerk and Luijten (1954,1956). It hydrolyses rapidly in aqueous medium to form triphenyltin hydroxide. Although of the organotin compounds it is the one best tolerated by plants, it is used mainly for the protection of field crops (sugar beet, potato). In certain cases, it causes phytotoxic damage, even in potatoes. This phytotoxicity can be reduced by combination with maneb, and a synergistic effect has even been detected between the two active substances (Hartel, 1964). The combination is marketed under the name Brestan . 

The iV-phenylformamido group in these compounds is easily cleaved by hydrolysis, iV-phenylformamide and an organotin hydroxide being formed. The tin-nitrogen bond is also broken by triphenyltin hydride. The products are 7V-phenylformamide and a compound containing a tin-tin bond, e.g., in the case of triethyl(AT-phenylformamido)tin, l,l,l-triethyl-2,2,2-triphenyl-ditin. 

The idea of using organotin compounds as ionophores was based on the fact that since, like carbon, tin forms covalent bonds via sp hybridization, and with the presence of empty d orbitals, it can coordinate with up to three extra electron-donating substituents, such as Lewis-basic anions. It was Selwyn, in 1970,9.10 ujal (ook advantage of this property and showed clearly the direct role of the trimethyltin, tri-n-propyltin, tri-n-butyltin, and triphenyltin chlorides on the active chloride transport mediated in mitochondrial membranes, as shown in Figure 3.4.5. It was also shown in this study that the mediation is based on chloride-hydroxide antiporter transport. This fact was verified many years later, as Simon showed, based on NMR and other studies, that indeed these compounds act as neutral carriers in liquid polymeric membranes. ... 

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