Alkylation of the sodium salt of dibenzyl malonate (I) with 1-bromo-3-phenylpropane (II) afforded the (phenylpropyl)malonate (III). The benzyl ester groups of (III) were removed by hydrogenolysis in the presence of Pd/C to produce the intermediate malonic acid (IV). Subsequent condensation of diacid (IV) with formaldehyde in the presence of piperidine proceeded with concomitant decarboxylation, yielding 2-methylene-5-phenylpentanoic acid (V). Addition of HBr to the unsaturated acid (V) gave bromide (VI). Condensation of (VI) with thiophenol (VIII), prepared by nucleophilic displacement of 4-(4-chlorobenzoyl)pyridine (VI) with sodium hydrogen sulfide, furnished the sulfide adduct (IX). This was oxidized to the corresponding sulfone (X) by treatment with Oxone(R). Conversion of (X) to the desired hydroxamic acid was carried out by coupling with O-tert-butyldimethylsilyl hydroxylamine, followed by deprotection of the resulting O-silyl hydroxamate (XI) with tetrabutylammonium fluoride.

Alkylation of the sodium salt of dibenzyl malonate (I) with 1-bromo-3-phenylpropane (II) afforded the (phenylpropyl)malonate (III). The benzyl ester groups of (III) were removed by hydrogenolysis in the presence of Pd/C to produce the intermediate malonic acid (IV). Subsequent condensation of diacid (IV) with formaldehyde in the presence of piperidine proceeded with concomitant decarboxylation, yielding 2-methylene-5-phenylpentanoic acid (V). Addition of HBr to the unsaturated acid (V) gave bromide (VI). Condensation of (VI) with thiophenol (VIII), prepared by nucleophilic displacement of 4-(4-chlorobenzoyl)pyridine (VI) with sodium hydrogen sulfide, furnished the sulfide adduct (IX). This was oxidized to the corresponding sulfone (X) by treatment with Oxone(R). Conversion of (X) to the desired hydroxamic acid was carried out by coupling with O-tert-butyldimethylsilyl hydroxylamine, followed by deprotection of the resulting O-silyl hydroxamate (XI) with tetrabutylammonium fluoride.