1,2-dithiolane-3-pentanoic acid 1077-28-7 5-(1,2-dithiolan-3-yl)pentanoato InChI=1/C8H14O2S2/c9-8(10)4-2-1-3-7-5-6-11-12-7/h7H,1-6H2,(H,9,10