Medicinal foodstuffs. XVII. Fenugreek seed. (3): structures of new furostanol-type steroid saponins, trigoneosides Xa, Xb, XIb, XIIa, XIIb, and XIIIa, from the seeds of Egyptian Trigonellafoenum-graecum L

Six new furostanol-type steroid saponins called trigoneosides Xa, Xb, XIb, XIIa, XIIb, and XIIIa were isolated from the seeds of Egyptian Trigonella foenum-graecum L. (Leguminosae) together with six known furostanol-type steroid saponins: trigoneosides Ia, Ib, and Va, glycoside D, trigonelloside C, and compound C. The structures of trigoneosides Xa, Xb, Xlb, XIIa, Xllb, and XIIIa were determined on the basis of chemical and physicochemical evidence as 26-O-beta-D-glucopyranosyl-(25S)-5alpha-furostane-2alpha+ ++,3beta,22xi,26-tetraol 3-O-alpha-L-rhamnopyranosyl(1-->2)-,beta-D-glucopyranoside, 26-O-beta-D-glucopyranosyl-(25R)-5alpha-furostane-2 alpha,beta,22xi,26tetraol 3-O-alpha-L-rhamnopyranosyl(l -->2)-beta-D-glucopyranoside, 26-O-beta-D-glucopyranosyl-(25R)-5alpha-furostane2alpha++ +,beta,22xi,26-tetraol 3-O-beta-D-xylopyranosyl(l -->4)-beta-D-glucopyranoside, 26-O-beta-D-glucopyranosyl-(25S)-furost-4-ene-3beta,22xi,26- triol 3-O-Ca-L-rhamnopyranosyl(1-->2)-beta-D-glucopyranoside, 26-O-beta-D-glucopyranosyl-(25R)-furost-4-ene-3beta,22xi+ ++,26-triol 3-O-alpha-L-rhamnopyranosyl(1-->2)-beta-D-glucopyranoside, and 26-O-beta-D-glucopyranosyl(25S)-furost-5-ene-3beta,22xi,26-t riol 3-O-alpha-L-rhamnopyranosyl(1-->2)-beta-D-glucopyranosyl (1-->3)-beta-D-glucopyranosyl(1--4)]-beta-D-glucopyranoside, respectively.     

Spirostanol sapogenins from the underground parts of Tupistra chinensis

Chemical examination of the underground parts of Tupistra chinensis led to the isolation of two new 5beta-spirostane type steroidal sapogenins, tupichigenin B (1) and C (2), together with two known steroidal sapogenins, ranmogenin A (3) and delta25(27)-pentrogenin (4). The structures of 1 and 2 were established as spirost-25(27)-ene-1beta,3beta,4beta,5beta,6b eta-pentaol and 1beta,2beta,3beta,4beta,5beta-pentahydroxyspi rost-25(27)-en-6-one, respectively, on the basis of detailed analysis of their physical and spectral data.     

A new cerebroside from fruits of Ailanthus altissima Swingle

A new cerebroside and three known cycloartan triterpenes were isolated from fruits of Ailanthus altissima Swingle. Their structures were identified as 1-O-beta-D-glucopyranosyl-(2S, 3R, 4E, 9E)-2-(2'R-hydroxyhexadecenoy)-4, 9-octadecadiene-1, 3-diol (1), 9, 19-cyclolanost-23 (Z)-ene-3beta, 25-diol (2), cycloart-25-ene-3beta, 24R-diol (3), and cycloart-25-ene-3beta, 24S-diol (4) by means of chemical and spectroscopic analysis. Compounds 2, 3, and 4 were isolated from genus Ailanthus for the first time. The analgesic activity of 1 was also evaluated.     

Studies on Balanites aegyptiaca fruits, an antidiabetic Egyptian folk medicine

An aqueous extract of mesocarps of the fruits of Balanites aegyptiaca exhibited a prominent antidiabetic activity by oral administration in streptozotocin induced diabetic mice. From one of the active fractions of this extract, two new steroidal saponins were isolated, and their structures were determined as 26-O-beta-D-glucopyranosyl-(25R)-furost-5-ene-3 beta,22,26-triol 3-O-[alpha-L-rhamnopyranosyl-(1----2)]-[beta-D-xylopyranosyl-(1---- 3)]-[alpha-L-rhamnopyranosyl-(1----4)]-beta-D-glucopyranoside and its 22-methyl ether. In addition, two known saponins, 26-O-beta-D-glucopyranosyl-(25R)-furost-5-ene-3 beta,22,26-triol 3-O-(2,4-di-O-alpha-L-rhamnopyranosyl)-beta-D-glucopyranoside and its methyl ether were isolated and identified. It was revealed that the individual saponins did not show antidiabetic activity, while the recombination of these saponins resulted in significant activity. From an ethanolic extract of the epicarps, two known flavonol glycosides, isorhamnetin-3-O-robinobioside and isorhamnetin-3-O-rutinoside were isolated and identified.     

Cimiracemoside a: A new cyclolanostanol xyloside from the rhizome of Cimicifuga racemosa

A new 9,19-cyclolanostane-type triterpene xyloside (1), from the rhizomes of Cimicifuga racemosa, has been isolated together with four known saponins; cimiaceroside A, 25-O-methylcimigenol-3-O-beta-D-xylopyranoside, 27-deoxyactein and 23-O-acetylshengmanol-3-O-beta-D-xylopyranoside. The structure of the new compound was established as 16beta,23:22beta,25-diepoxy-12-acetoxy-3beta,23,24b eta-trihydroxy-9,19-cyclolanost-7-ene-3-O-beta-D-xylopyranoside . For the structure elucidation, 1D- and 2D-NMR experiments and high resolution electrospray ionization Fourier transformation mass spectrometry (HRESIFTMS) were used.     

Synthesis of the aglycone of the shark repellent pavoninin-4 using remote functionalization

[reaction: see text] The aglycone of shark repellent pavoninin-4, (25R)-5alpha-cholestan-3alpha,15alpha,26-triol 26-acetate 1a, was synthesized from (25R)-cholest-5-en-3beta,26-diol 4 (26-hydroxycholesterol) in eight steps in 18% overall yield. Breslow's remote functionalization strategy was used as a key step to introduce the C-15alpha alcohol on a steroid D ring. An efficient synthesis of the 26-hydroxycholesterol from the 16beta hydroxyl steroid, (25R)-cholest-5-ene-3beta,16beta,26-triol (3a), is also reported.     

Total synthesis of methyl protodioscin: a potent agent with antitumor activity

Methyl protodioscin (1), otherwise known as 3-O-[alpha-L-rhamnopyranosyl-(1-->2)-[alpha-L-rhamnopyranosyl-(1-->4)]-beta-d-glucopyranosyl]-26-O-[beta-D-glucopyranosyl]-22-methoxy-25(R)-furost-5-ene-3 beta,26-diol, has been synthesized for the first time from diosgenin through nine steps in an overall yield of 7.8%.     

New polyhydroxylated furostanol saponins with inhibitory action against NO production from Tupistra chinensis rhizomes

Two furostanol saponins were obtained from the rhizomes of Tupistra chinensis Bak. Their structures were determined as 5beta-furost-delta(25(27))-en-1beta,2beta,3beta,4beta,5beta,7alpha,22xi,26-octaol-6-one-26-O-beta-D-glucopyranoside (1) and 5beta-furost-delta(25(27))-en-1beta,2beta,3beta,4beta,5beta,6beta,7alpha,22xi,26-nonaol-26-O-beta-D-glucopyranoside (2), on the basis of chemical and spectroscopic evidence. Both compounds displayed marked inhibitory action against NO production in rat abdomen macrophages induced by lipopolysaccharide (LPS) at 40 microg/mL.     

Evaluation of the antiviral and antimicrobial activities of triterpenes isolated from Euphorbia segetalis

A phytochemical reinvestigation of the whole plant of Euphorbia segetalis yielded five tetracyclic triterpenes: 3beta-hydroxy-cycloart-25-en-24-one (1), cycloart-25-ene-3beta,24-diol (2), cycloart-23-ene-3beta,25-diol (3), lanosta-7,9(11),24-trien-3beta-ol (4) and lanosta-7,9(11),24(31)-trien-3beta-ol (5). beta-acetoxy-cycloart-25-en-24-one (1a) and glutinol (6), lupenone (7), dammaranodienol (9), cycloartenol acetate (10), 24-methylenecycloartanol acetate (11) and beta-sitosterol (12), isolated previously, were evaluated for their antiviral activities against Herpes simplex virus (HSV) and African swine fever virus (ASFV). Lupenone exhibited strong viral plaque inhibitory effect against HSV-1 and HSV-2. The in vitro antifungal and antibacterial activities of la, cycloart-23-ene-3beta,25-diol, 3-acetate (3a) and 6-12 were also investigated.     

Cycloartane triterpenes from Euphorbia tuckeyana

Investigation of the acetone extract of the whole plant of Euphorbia tuckeyana afforded a new cycloartane-type triterpene named as cyclotucanol. Its structure was established as cycloartane-24-methylene-3beta,25-diol (1). The known cycloartane triterpenes cycloeucalenol (2), 3beta-hydroxycycloart-25-en-24-one (3), cycloart-25-ene-3beta,24-diol (4), 25,26,27-trisnor-3beta-hydroxycycloartan-24-al (5) and cycloart-23-ene-3beta,25-diol (6) were also isolated and identified.     

Two new triterpenes from the seeds of Trichosanthes cucumeroides

Two new triterpenes named 7-oxodihydrokarounitriol (1) and 7,11-dioxodihydrokarounidiol (2), and one known triterpene, 7-oxodihydrokarounidiol (3), were isolated from the unsaponifiable matter of the seeds of Trichosanthes cucumeroides. The structures of 1 and 2 were elucidated as (3alpha, 11beta, 13alpha, 14beta, 20alpha)-3,11,29-trihydroxy-13-methyl-26-norolean-8-ene-7-one, and (3alpha,13alpha,14beta,20alpha)-3,29-dihydroxy-13-methyl-26-norolean-8-ene-7,11-dione on the basis of extensive NMR (1H, 13C, 1H-1H COSY, DEPT, HMQC, HMBC and NOESY) and MS studies.     

Two new steroidal glucosides from Ophiopogon.japonicus （L.f.） Ker-Gawl

Two new steroidal glucosides, 26-O-β-D-glucopyranosyl （25S）-furost-5-ene-1β,3β,22α,26-tetraol l-O-β-D-xylopyranosyl- （1 → 3）-[α-h-rhamnopyranosyl-（1 → 2）]-[β-D-fueopyranoside and （25R） spirost-5-ene-3β,14α-diol-3-β-O-β-L-rhanmopyranosyl- （1 → 2）-[β-D-xylopyranosyl（1 → 4）]-[-β-D-glucopyranoside, were isolated from the Ophiopogon japonicus （L.f.） Ker-Gaw. Their structures were elucidated by spectroscopic methods.     

A new cytotoxic cholesterol sulfate from marine sponge Halichondria rugosa

A new steroid, 24xi,25-dimethyl-3alpha-hydroxyl-cholest-5-ene-2beta-ol sodium sulfate (1), together with a known steroid, 24xi,25-dimethyl-cholest-5-ene-2beta,3alpha-diol disodium sulfate (2), was isolated from the ethanol extract of marine sponge Halichondria rugosa. Their structures were elucidated on the base of spectroscopic analysis. Both compounds showed cytotoxicity to four human cancer cell lines (BEL-7402, HT-29, SPC-A1 and U-251) with IC(50) values between 6.5 and 23.1 microM.     

Steroidal oligoglycosides from the seeds of Allium tuberosum

Three new spirostanol steroidal oligoglycosides, together with a known oligoglycoside, were obtained from the seeds of Allium tuberosum after enzymatic hydrolysis of furostanol saponin fraction by beta-glucosidase. On the basis of spectroscopic analysis, the structure of new spirostanol oligoglycosides were elucidated as (25S)-spirost-5-ene-2alpha,3beta-diol 3-O-alpha-L-rhamnopyranosyl-(1-->4)-[alpha-L-rhamnopyranosyl-(1-->2)]-be ta-D-glucopyranoside, (25S)-spirostane-3beta,5beta,6alpha-triol 3-O-alpha-L-rhamnopyranosyl-(1-->4)-beta-D-glucopyranoside, and (25S)-5beta-spirostane-3beta,6alpha-diol 3-O-alpha-L-rhamnopyranosyl-(1-->4)-beta-D-glucopyranoside.     

Steroids of the spirostan and furostan series from Nolina microcarpa I. Structures of nolinospiroside C and nolinofurosides A and C

In addition to the know steroid sapogenin (25S)-ruscogenin (I), three new glycosides have been isolated from the leaves ofNolina microcarpa S. Wats. (family Dracaenacea), and the following structures are suggested for them: (25S)-spirost-5-ene-1β,3β-diol 1-O-β-D-fucopyranoside (nolinospiroside C, II), (25S)-furost-5-ene-1β,3β,22α,26-tetraol 1-O-β-D-fucopyranoside (nolinofuroside A, III), and (25S)-furost-5-ene-1β, 3β, 22α, 26-tetraol 1-O-β-D-fucopyranoside 26-O-β-D-glucopyranoside (nolinofuroside C, V).     

New steroidal alkaloids from Fritillaria imperialis and their cholinesterase inhibiting activities

Two new cevanine steroidal alkaloids, impericine (1) and forticine (2) along with known bases delavine (3), persicanidine A (4), and imperialine (5) were isolated from the bulbs of Fritillaria imperialis. The structures of impericine (1) [(20R,22S,25S)-5alpha-cevanin-23-ene-3beta,6beta,16beta-triol] and forticine (2) [(20S,22S,25S)-5alpha-cevanine-3beta,6beta-diol] were determined with the help of spectroscopic studies. These steroidal bases showed anti-acetylcholinesterase and anti-butyrylcholinesterase inhibitory activity.     

An acetoxygenated analogue of ergosterol from a soft coral of the genus Lobophytum

Chemical investigation of a soft coral of the genus Lobophytum of the Andaman and Nicobar coasts resulted in the isolation of a new marine sterol acetate, (24S)-ergostane-3beta,5alpha,6beta,25-tetraol-3,6,25-triacetate (1) and of two known sterol glycosides 3beta,4alpha-dihydroxypregn-20-ene-4-O-beta-D-arabinopyranoside and 24-methylenecholest-5-ene-3beta,7beta, 16beta-triol-3-O-alpha-L-fucopyranoside-7beta-acetate. The structures of the compounds were elucidated based on spectral studies and chemical conversions.     

Structural revision of terpenoids with a (3Z)-2-methyl-3-penten-2-ol moiety by the synthesis of (23E)- and (23Z)-cycloart-23-ene-3beta,25-diols

Synthesis of (23E)-cycloart-23-ene-3beta,25-diol (1) and its 23Z-isomer 2 was achieved by using cycloartenol as a starting material, thus revising the proposed structure of natural 2 to 1 unequivocally. These synthetic studies revealed that the structural revision (Z-form --> E-form) should also be applied to terpenoids such as (23Z)-3beta-acetoxyeupha-7,23-diene-25-ol, (23Z)-tirucalla-7,23-diene-3beta,25-diol, quadrangularol A, quadrangularic acid K, and daurichromene C.     

Steroids of the spirostan and furostan series from Nolina microcarpa I. Structures of nolinospiroside C and nolinofurosides A and C

In addition to the know steroid sapogenin (25S)-ruscogenin (I), three new glycosides have been isolated from the leaves ofNolina microcarpa S. Wats. (family Dracaenacea), and the following structures are suggested for them: (25S)-spirost-5-ene-1,3-diol 1-O--D-fucopyranoside (nolinospiroside C, II), (25S)-furost-5-ene-1,3,22,26-tetraol 1-O--D-fucopyranoside (nolinofuroside A, III), and (25S)-furost-5-ene-1, 3, 22, 26-tetraol 1-O--D-fucopyranoside 26-O--D-glucopyranoside (nolinofuroside C, V).M. V. Frunze Simferopol' State University. Institute of Chemistry of Plant Substances, Uzbek Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 672–678, September–October, 1991.     

Potent tyrosinase inhibitors from Trifolium balansae

Trifolium balansae (Leguminosae) yielded a phytylester, phytyl-1-hexanoate, three steroids, stigmast-5-ene-3 beta,26-diol, stigmast-5-ene-3-ol and campesterol, and an alcohol, pentacosanol which were reported for the first time from T.balansae. The structures of the isolates were determined by 1D and 2D NMR techniques and MS spectroscopy. Compounds 1-5 were tested for their enzyme tyrosinase activity. While compounds 1 and 5 did not show any inhibition against the enzyme tyrosinase, compounds 2, 3, and 4 exhibited potent inhibition against tyrosinase. Highly potent (IC50 = 2.39 microM) inhibition was found by compound 2, when compared with the standard tyrosinase inhibitors Kojic acid and L-mimosine.