Total synthesis and analgesic activity of 6-fluoroindan-1-acetic acid and its 3-oxo derivative.

6-Fluoro-3-oxo-indan-1-acetic acid (5) and 6-fluoroindan-1-acetic acid (6) were conveniently synthesised from 3-fluorobenzaldehyde in four and five steps, respectively. The structures of these new compounds and two other intermediates, 3-fluorobenzylidine-bis-acetoacetate (2) and 3-fluoro-beta-phenyl glutaric acid (3) were elucidated by spectroscopic means, notably, HRMS, 1D and 2D NMR. The analgesic activity of compounds 5 and 6 were assessed by the acetic acid induced writhing in Swiss albino mice.