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A series of diphenyl-neolignan honokiol analogs were synthesized and investigated for their inhibitory activities against NO production in LPS-activated BV-2 microglial cells. Nitrile oxide cycloaddition constructed isoxazole skeleton from oxime 5 and condensation of 4-chromone and alkylhydrazine generated the pyrazole. Compound 15b and 16a exhibited stronger inhibitory activities with IC50 = 8.9 and 1.2 µM, respectively, than that of honokiol. An enantioselective synthetic route to hydroxywilfordic acid was developed. Hydroxywilfordic acid was a key fragment of sesquiterpene pyridine alkaloids such as wilfortrine. To afford (S)-isomer α-hydroxy-α-methyl acid, the asymmetric cyanation by Jacobsen (R,R)-amino-thiourea and hydrolysis was used. Naturally derived hydroxywilfordate and hydroxywilfordic acid prepared by methanolysis and hydrolysis of wilfortrine were proven to be the (R)-isomer upon comparison with the synthetic compound.