title: Galloyl, caffeoyl and hexahydroxydiphenoyl esters of dihydrochalcone glucosides from Balanophora tobiracola.
abstract: Seven galloyl, caffeoyl and (S)-hexahydroxydiphenoyl (HHDP) esters of dihydrochalcone glucosides were isolated from Balanophora tobiracola; based on spectroscopic and chemical evidence, their structures were determined to be 6''-O-galloyl-, 3'',4''-di-O-galloyl-, 4'',6''-di-O-galloyl-, 4'',6''-O-(S)-HHDP-, 3''-O-galloyl-4'',6''-O-(S)-HHDP-, 3''-O-caffeoyl-4'',6''-O-(S)-HHDP-3-hydroxyphloretin 4'-O-beta-D-glucosides and 3''-O-galloyl-4'',6''-O-(S)-HHDP-phloretin 4'-O-beta-D-glucoside, respectively. By contrast, these compounds were not found in the taxonomically related B. japonica. The 3''-galloyl-4'',6''-HHDP esters of the dihydrochalcone glucosides showed strong inhibitory activities against alpha-glucosidase. Four known compounds were also isolated namely, (+/-)-eriodictyol 7-O-beta-D-glucoside, 1-O-caffeoyl-3-O-galloyl-beta-D-glucose, phloretin 4'-O-beta-D-glucoside, and 3-hydroxyphloretin 4'-O-beta-D-glucoside.
authors.affiliation: Graduate School of Biomedical Sciences, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki 852-8521, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Tanaka
authors.forename: Rami
authors.initials: R
authors.lastname: Uehara
authors.forename: Kaori
authors.initials: K
authors.lastname: Nishida
authors.forename: Isao
authors.initials: I
authors.lastname: Kouno
mesh_terms: D031111:Balanophoraceae / Q000737:chemistry*; D002599:Chalcone / Q000031:analogs & derivatives* / Q000737:chemistry / Q000302:isolation & purification*; D047188:Chalcones; D005960:Glucosides / Q000737:chemistry / Q000302:isolation & purification*; D015394:Molecular Structure; D035261:Plant Components, Aerial / Q000737:chemistry
chemical_list: D047188:Chalcones; D005960:Glucosides; D002599:Chalcone; C015812:dihydrochalcone