Esterified derivative of thiosalicylic acid combining a soft nucleophilic –SH with a methyl ester handle. It is a versatile intermediate for:
Pharmaceutical actives: key building block for the anti-cancer Ras-inhibitor farnesyl thiosalicylic acid (FTS) and its analogues, prepared via base-catalysed alkylation with farnesyl bromide followed by mild hydrolysis ;
Agro-chemicals: precursor to thio-ether fungicides and insecticides through Cu-catalysed cross-coupling;
Optical materials: chain-transfer agent in RAFT polymerisation for high-refractive-index poly(aryl sulfide) resins (nD ≈ 1.68) used in 5G lens and OLED encapsulation films;
Surface functionalisation: forms densely packed SAMs on gold, lowering surface energy and enhancing SERS sensitivity for mercury detection;
Fragrance & flavour: trace additive (<1 ppm) for roasted, coffee-like notes (FEMA 4768).
Store under nitrogen at 2–8 °C, away from light and oxidants; avoid strong bases to prevent thio-ester hydrolysis.
