Entymatic transfer of the caffeic acid to the glucosyl moiety of caffeic sugar esters

• Project/Area Number: 11660159
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: 林産学
• Research Institution: Iwate University
• Principal Investigator: OTA Michikazu Iwate University, Faculty of Agriculture, Professor, 農学部, 教授 (80111160)
• Co-Investigator(Kenkyū-buntansha): KOFUJITA Hisayoshi Iwate University, Faculty of Agriculture, Lecturer, 農学部, 講師 (40270798)
• Project Period (FY): 1999 – 2001
• Project Status: Completed (Fiscal Year 2001)
• Budget Amount: ¥3,800,000 (Direct Cost: ¥3,800,000); Fiscal Year 2001: ¥500,000 (Direct Cost: ¥500,000); Fiscal Year 2000: ¥500,000 (Direct Cost: ¥500,000); Fiscal Year 1999: ¥2,800,000 (Direct Cost: ¥2,800,000)
• Keywords: Paulownia tomentosa Steud. / Caffeoyltransferase / 2-oxoisoacteoside / 3,4-di-O-allylcaffeic acid / 1-(3,4-diallyloxyphenyl)-2-hydroxy-1-ethanone / Deprotection / acetyl group / allyl group / 2-oxo-2-(3,4-di-hydroxyphenyl)-ethyl 3-O-α-L-rhamnpyranosyl-6-O-caffeoyl-β-D-glucopyranoside / 1-(3',4'-diallyloxyphenyl)-2-hydroxy-1-ethanone / 合成 / アシル基転移酵素 / カフェー酸糖エステル / アクテオシド / 4-O-Caffeoyl-D-glucopyranoside / 桐葉 / ポリフェノール / カフェオイル補酵素A / アシル基授与体 / トメントシドA

Research Abstract

The preparation of caffeoyl : CoA ligase and caffeoyltransferase from the leaves of Paulownia tomentosa Steud. is still in progress in this stage of research, but as another aspect of this study, the following results were obtained ; 2-oxoisoacteoside (2-oxo-2-(3,4-dihydroxyphenyl)-ethyl 3-O-α-L-rhamnopyranosyl-6-O- caffeoyl-β-D-glucopyranoside) was chemically synthesized from glucose in the 21 reaction steps (main 13 steps) with total yield of 7.4 %. l,2-O-acetyl-3-O-(2,3,4-tri-O-acetyl-α-L-rhamnopyranosyl) -6-O-acetyl-D-glucopyranose (3) was prepared from 1,2 : 5,6-di-O-isopropylidene-3-O-(2,3,4-tri-O-acetyl-L-rhamnopyranosyl)-D- glucofuranose in the 5 reaction steps with yield of 47 %. 3,4-di-O-allylcaffeic acid(2") was prepared from protocatechuic acid in the 2 reaction steps with yield of 67 %. 1,2-O-acetyl-3-O-(2,3,4-tri-O-acetyl-α-L-rhamnosyl) -4-O-(3,4-O-allyl caffeoyl)-6-O-acetyl-D-glucopyranose (4) was prepared from compounds 3 and 2" with yield of 98 % in the presence of DCC, DMAP, and DMAP-HCl. 2-oxo-2-(3',4'-diallyloxyphenyl)-ethyl 2-O-acetyl-3-O-(2,3,4-tri-O-acetyl-α-L-rhamnopyranosyl)-4-O-(3,4-O-diallyl caffeoyl)-6-O-acetyl-D-glucopyranoside was prepared from compound 4 and 1-(3,4-diallyloxyphenyl)-2-hydroxy-1-ethanone (2"') in the 3 reaction steps with yield of 53 %. Compound 2" was prepared from 2-chloroacetyl catechol in the 3 reaction steps with yield of 44 %. Compound 5 was deprotected with yield of 76 %, giving 2-oxoisoacteoside. Deprotection of acetyl group resulted in migration of caffeoyl group to C-6-OH of glucose moiety in compound 5.