Acylation of 3-methyl-2,3-bis(trimethylsiloxy)-1-butene (PhLi) with (E)-2-methyl-2-butenoyl chloride gives the corresponding 3(2H)-furanone derivative, which can be readily converted to the naturally occurring antitumor agent Geiparvarin by two steps. Recently, considerable attention has been attracted to the synthesis of Geiparvarin (l_),laod a constituent of Ge.ijera pamifbra Lindl, 2a-c because of its unique structure jointing 3(2H)- furanone and cumarin skeletons as well as biological activity against in vitro human carcinoma of the nasopharynx.lay3 The synthetic methods of l_ reported so far la-d involve a multitude of steps before the construction of 3(2H)-furanone skeleton. Moreover, two of the methods la,d suffer from the formation of E/Z olefinic mixture. We report here a novel and more simplified (three steps) synthetic route to 1 by application of one-pot construction of 2,2-dimethyl-5-(1methyl-1-propenyl)-3(2H)-furanone (4) from readily available starting materials such as 3-methyl-2,3-bis(trimethylsiloxy)-l-butene (s)4 and (E)-2-methyl-2-butenoyl chloride (3). Selective bromination of 4 and the combination with 7-hydroxycumarin (7) successfully led to 1 in good yield.