(7R)-2,2,3,3,10-pentamethyl-7-[(2S)-pent-4-yn-2-yl]-9,9-bis(propan-2-yl)-4,8-dioxa-3,9-disilaundecane

(7R)-7-[(2S)-hex-4-yn-2-yl]-2,2,3,3,10-pentamethyl-9,9-bis(propan-2-yl)-4,8-dioxa-3,9-disilaundecane