A series of yakuchinone B 1f and its analogs 1a-e was synthesized and evaluated for free radical scavenging, suppression of LPS-induced NO generation, cytotoxicity and anti-excitotoxicity in vitro. Compound 1c exhibited potent anti-excitotoxicity, while all compounds 1a-f showed considerable effects of free radical scavenging, suppression of LPS-induced NO generation, and cytotoxicity in microglia.