Malonyl-Caffeoylquinic Acids and Malonyl-Flavonoid-Glucosides from Three Edible Apiaceae Plants <i>Anthriscus Cerefolium</i>, <i>Anthriscus Sylvestris</i>, and <i>Chaerophyllum Bulbosum</i>

Novel compounds, including four isomeric monomalonyl-dicaffeoylquinic acids (<b>4</b>-<b>7</b>), one dimalonyl-dicaffeoylquinic acid (<b>9</b>), and one flavonoid-dimalonyl-glucoside (<b>8</b>), along with three known flavonoid-monomalonyl-glucosides (<b>1</b>-<b>3</b>), were discovered in closely related edible Apiaceae plants: <i>Anthriscus cerefolium</i>, <i>Anthriscus sylvestris</i>, and <i>Chaerophyllum bulbosum</i>. Their structures were elucidated through comprehensive HPLC-UV-HR-MS/MS and NMR analyses, and isomeric malonyl-dicaffeoylquinic acids (<b>4</b>-<b>7</b>) were differentiated based on HPLC-MS/MS fragmentation characteristics. The study confirmed organ- and vegetation phase-specific accumulation, identifying optimal plant tissues for targeted isolation using a one-step preparative HPLC method. Malonyl-dicaffeoylquinic acids <b>4</b> and <b>9</b> exhibited significant cytotoxicity to nontumorous Vero E6 cells <i>in vitro</i> (IC₅₀ < 10 μM). At the same time, the isolated compounds displayed structure-specific DPPH radical scavenging activity, underscoring their dual biological relevance.