Baimantuoluosides D-G, four new withanolide glucosides from the flower of Datura metel L.

Abstract

In our search for bioactive anti-psoriasis compounds from the flower of Datura metel L, we isolated four new withanolide glucosides, baimantuoluosides D, E, F and G (1-4). The structures of the new compounds are (5alpha,6alpha,7beta,22R)-5,6,7,27-tetrahydroxy-1-oxowitha-2,24-dien-27-O-beta-D-glucopyranoside (1), (5alpha,6beta,7alpha,22R)-5,6,7,27-tetrahydroxy-1-oxowitha-2,24-dien-27-O-beta-D-glucopyranoside (2), (5alpha,6beta,7alpha,12beta,22R)-5,6,7,12,27-pentahydroxy-1-oxowitha-2,24-dien-27-O-beta-D-glucopyranoside (3), and (5alpha,6beta,22R)-5,6,27-trihydroxy-1-oxowitha-2,24-dien-27-O-beta-D-glucopyranoside (4) on the basis of chemical and physicochemical evidence.

Five Withanolides from the Leaves of Datura metel L. and Their Inhibitory Effects on Nitric Oxide Production

“…Withanolides have been studied for treating psoriasis as the main constituents of the effective part of flowers of D. metel [11,12]. Baimantuoluolines A-J, and baimantuoluosides A-H were also isolated and reported [8,[13][14][15][16][17][18]. However, the dry flowers of D. metel have the disadvantages of long florescence and low yield in comparison to its leaves.…”

Chemical composition and cytotoxicity of the essential oil from different parts of Datura metel L.

“…Our research group has extensively researched on chemical constituents and pharmacological activities for many years, including multiple parts of D. metel L. such as leaves, seeds. A variety of compounds such as alkaloids, flavonoids and withanolides have been isolated from the plant (Yang et al 2010a(Yang et al , 2010b(Yang et al , 2013Kuang et al 2011). We also found that the flowers of D. metel L. had effect of anti-inflammatory, anti-itch, anti-proliferative and some other pharmacological effects and the seeds have anti-proliferation and potential immune suppression activities ).…”

Two New Withanolide Lactones from Flos Daturae

“…The double doublet at δ 3.47 (1H, dd , J = 10.9, 4.5 Hz) was characteristic for a 12 β -hydroxywithanolide [4]. H-22 resonated as a double triplet at δ 4.62 (1H, dt , J = 12.9, 3.4 Hz), revealing a R configuration at C-22 [5,6]. …”

“…Flos Daturae has been found to be rich in tropane alkaloids [2]. Besides, a number of withanolides have also been isolated from Flos Daturae [3,4,5,6,7,8]. Recently Flos Daturae has been used clinically for the treatment of psoriasis in China [9].…”

“…However, its active constituents and pharmacological effects related to the treatment of psoriasis were not fully elucidated. As a part of a continuing project to study the active constituents of Flos Daturae for psoriasis [6,7,8], we investigated the 50% ethanol eluate fraction from a macroporous resin of the flowers of D. metel . Our extraction and separation method can greatly enrich fractions in withanolide compounds so trace withanolides can be isolated.…”