A New Phytoecdysteroid from Ajuga taiwanensis

Abstract

Many plants contain ecdysteroids, polyhydroxysteroids with a cis-fused A/B ring junction and 14a-hydroxy-7-ene-6-one system, structurally related with ecdysone, the biosynthetic precursor of the insect moulting hormone.1) These compounds exhibit interesting physiological activities such as regulation of moulting in insects, hormonal functions involve regeneration, metamorphosis, reproduction and differentiation in all arthropods, and antiulcer, antirheumatic, insulin regulation and diuretic or tonic effects in mammals. 2)Among the numerous plants containing phytoecdysteroids, those pertaining to Ajuga genus are unique for the great variety of such compounds produced.3) Species belonging to genus Ajuga have been used as folk medicinal plants as anthelmintic against intestinal disorders, antifungal, hypoglycaemic, antitumor and antimicrobial agents. 4,5) Furthermore, it has also been reported that some species of this genus were especially used as diuretic agents, as a remedy for fever, toothache, dysentery and hypertension. 6) Earlier chemical investigations have led to the isolation of clerodane diterpenoids, 7-9) ecdysteroids, 3,5,10,11) flavonoids, 12) iridoids [13][14][15] and triglycerides.16) The compounds isolated from the genus Ajuga, exert a broad spectrum of biological and pharmacological actions such as cytotoxic, anti-mitotic, anti-bacterial, cardiotonic, vasorelaxing, antifungal and antifeedant and insect growth-inhibitions. These facts encouraged us to investigate the chemical constituents of an Ajuga species A. taiwanensis NAKAI ex MURATA (Labiatae) mainly distributed in the Taiwan, Philippines and Ryukyus which has been often used for the treatment of hepatitis and hepatoma in Taiwanese folk medicine.17) The isolation of ajugalide A to D from title plant has recently been reported from our laboratories. In this paper, we now describe the isolation and structural elucidation of one new phytoecdysteroid, ajugalide-E (1) and twenty five known compounds. Results and DiscussionAjugalide-E (1) was isolated as an optically active, white amorphous solid, mp 210-212°C. The high-resolution fastatom bombardment mass spectrum (HR-FAB-MS) of 1 showed a pseudo molecular ion peak ([MϩH] . These data were consistent with the occurrence of characteristic side chain with g-lactone by similitude with 22-acetylcasterone signals. Additional functionalities included the signal of an olefinic proton at d 6.21 (br s) as well as nine methine protons and seven methylene groups and an acetyl methyl group also supported the basic skeleton of phytoecdysteroid. As shown in Table 1 the 1 H-and 13 C-NMR spectra for compound 1 showed a high analogy with those of 22-acetylcasterone with a cis fused A/B ring junction and 14a-hydroxy-7-ene-6-one skeleton 19) Results of two-dimensional correlation spectroscopy (2D-COSY) and the long-range 13 C-1 H correlation in heteronuclear multiple bond correlation (HMBC) experiments also confirmed that the planar structure of 1 was the same as 22-acetylcasterone (2). But the differences in...

In vitro production of metabolism-enhancing phytoecdysteroids from Ajuga turkestanica

“…HPLC-MS-ESI showed a molecular ion peak of [M + Na] + m/z 519.3 corresponding to C 27 H 44 O 8 . HPLC-MS-ESI and NMR data are in agreement with literature reported for the isolated ecdysteroids (Okuzumi et al 2005;Chan et al 2005;Darwish and Reinecke 2003).…”

“…The isolated phytoecdysteroids were identified by comparing physical, chemical and spectral data ( 1 H and 13 C NMR and ESI-MS) with reported data (Okuzumi et al 2005;Chan et al 2005;Darwish and Reinecke 2003). 1 H NMR (500 MHz) and 13 C NMR (125 MHz) spectra, all in CD 3 OD, were recorded on a Varian Inova 500 spectrometer (Varian Instruments, Palo Alto, CA), using TMS as the internal standard.…”

Diverse Secondary Metabolites from the Coral-Derived Fungus Aspergillus hiratsukae SCSIO 5Bn1003

“…Crystal data for 1: C 28 H 28 N 4 O 5 , M = 500.54, orthorhombic, space group P212121 (no. 19), a = 8.18580 (10) The final R 1 was 0.0675 (I > 2σ(I)) and wR 2 was 0.1981 (all data). The goodness of fit on F 2 was 1.074.…”

“…Its13 C NMR and DEPT data (Table1) showed the presence of 35 carbon resonances, including four methyls, eight methylenes, and fourteen methines (six olefinic carbons), as well as nine quaternary carbon atoms (two olefinic carbons, three carbonyls, and four aliphatic carbons). Detailed analysis of its 1D and 2D NMR allowed for the assignment of three partial structures, including a typical ecdysteroid substructure with a cis-fused A/B ring junction and a 14α-hydroxy-7-ene-6-one skeleton[9], a γ-lactone side chain[10], and a monosubstituted benzoate group. All the above data taken together indicated that 2 was structurally related to the γ-lactone phytoecdysteroids 29-norcyasterone[11], with the only difference being the hydroxy substitution at C-22.…”

The phytochemical, biological, and medicinal attributes of phytoecdysteroids: An updated review

“…A literature survey indicates that 29 new ecdysteroids have been reported from the Lamiaceae family. These are 28- epi -cyasterone [(22 R ,24 S ,25 S ,28 S ) 5 β -stigmast-7-ene-26-oic acid, 2 β ,3 β ,14,20,22,28-hexahydroxy-6-oxo- γ -lactone] ( 152 ), isolated from Eriophyton wallchii 115 , ajugalide-E ( 153 ) from Ajuga taiwanensis 116 , breviflorasterone ( 154 ), ajugacetalsterone C ( 155 ), ajugacetalsterone D ( 156 ) from Ajuga macrosperma var. breviflora 117 , decumbesterone A ( 157 ) 118 and ajugacetalsterone E ( 158 ) 119 isolated from Ajuga decumbens , 22-dehydrocyasterone-2-glucoside ( 159 ), ajugacetalsterone A ( 160 ) and ajugacetalsterone B ( 161 ), isolated from Ajuga nipponensis 120 , 25-hydroxy-atrotosterone A ( 162 ), 11-hydroxy-cyasterone ( 163 ), 11-hydroxy-sidisterone ( 164 ), turkesterone 22-acetate ( 165 ), 22 oxo-turkesterone ( 166 ), 11-hydroxy-Δ24-capitasterone ( 167 ) and turkesterone 20,22-acetonide ( 168 ), isolated from Ajuga turkestanica 121 , reptanslactone A ( 169 ), reptanslactone B ( 170 ) and sendreisterone ( 171 ), isolated from Ajuga reptans var.…”