title: Novel chemical synthesis of ginkgolic acid (13:0) and evaluation of its tyrosinase inhibitory activity.
abstract: A novel efficient synthesis of ginkgolic acid (13:0) from abundant 2,6-dihydroxybenzoic acid was successfully developed through a state-of-the-art palladium-catalyzed cross-coupling reaction and catalytic hydrogenation with an overall yield of 34% in five steps. The identity of the synthesized ginkgolic acid (13:0) was confirmed by nuclear magnetic resonance, mass spectrometry, infrared, and high-performance liquid chromatography. The reaction sequence of this method can be readily extended to the synthesis of other ginkgolic acids. The synthesized ginkgolic acid (13:0) exhibited promising anti-tyrosinase activity (IC₅₀ = 2.8 mg/mL) that was not correlated to antioxidant activity as probed by 1,1-diphenyl-2-picrylhydrazyl, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid), ferric reducing ability of plasma, and oxygen radical absorbance capacity assays. The synthetic strategy developed in this work will significantly facilitate biological studies of ginkgolic acids that have great potential applications in food and pharmaceuticals.
authors.affiliation: Department of Food Science and Nutrition, and ‡Fuli Institute of Food Science, Zhejiang University , 866 Yuhangtang Road, Hangzhou 310058, People's Republic of China.
authors.forename: Yuanqing
authors.initials: Y
authors.lastname: Fu
authors.forename: Shan
authors.initials: S
authors.lastname: Hong
authors.forename: Duo
authors.initials: D
authors.lastname: Li
authors.forename: Songbai
authors.initials: S
authors.lastname: Liu
mesh_terms: D000363:Agaricales / Q000201:enzymology; D000935:Antifungal Agents / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D004791:Enzyme Inhibitors / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology*; D005520:Food Preservatives / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D005656:Fungal Proteins / Q000037:antagonists & inhibitors* / Q000378:metabolism; D015394:Molecular Structure; D014442:Monophenol Monooxygenase / Q000037:antagonists & inhibitors* / Q000378:metabolism; D012459:Salicylates / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology*
chemical_list: D000935:Antifungal Agents; D004791:Enzyme Inhibitors; D005520:Food Preservatives; D005656:Fungal Proteins; D012459:Salicylates; C112485:ginkgolic acid; D014442:Monophenol Monooxygenase