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Extension of a structure–activity relationship study of the antitumor cytotoxicity of lipidic dialkynylcarbinols (DACs) is envisaged by formal methinylogation of one of the ethyndiyl moieties of the DAC warhead into the corresponding allenylalkynylcarbinol (AllAC) counterpart. External AllACs were directly obtained by methinylation of the parent DACs with formaldehyde in either the racemic or scalemic series. Isomers containing external progargyl and propynyl motifs were also prepared. Internal AllACs were obtained as racemic statistical mixtures of stereoisomers in two steps from the key C₅‐DAC rac‐TIPS‐C≡C‐CH(OH)‐C≡CH and aldehydes. Kinetic resolution of the (S)‐C₅‐DAC in 97 % ee and (R)‐C₅‐DAC in 99 % ee was achieved by sequential lipase‐mediated acetylation/hydrolysis using the Candida antartica lipase (Novozyme 435). The four internal AllAC stereoisomers were prepared by asymmetric …