Cardiotonic steroids with additional lactone rings

Stereochemical structural transformations of cardiosteroids to create in them additional lactone rings were studied. Creation of δ-lactones by reaction of a 3β-OH group and a 19-carboxylic group to give the corresponding A/B-trans cardiosteroids and creation of β-lactones by reaction of a 5β-OH group and a 19-COOH to give the corresponding A/B-cis steroids were studied. The new biologically active compounds 8(14)-dehydrobovogenin-19-carboxylic acid 3β-O-19-lactone, strophanthidine-19-carboxylic acid 5β-O-19-lactone, cymarin-19-carboxylic acid 5β-O-19-lactone, convallatoxin-19-carboxylic acid 5β-O-19-lactone, and strophalloside-19-carboxylic acid 5β-O-19-lactone were prepared.     

Synthesis of 6α-methyl-16α,17α-cyclohexano-19-norprogesterone from a 19-methyl-6-desmethyl precursor

After prolonged refluxing of 19-tosyloxy-16α,17α-cyclohexanopregn-5-en-3β-ol-20-one (3) with NaI in 2-propanol, the initially formed 19-iodo derivative (4) undergoes supraface migration of the CH₂I group from the C(10) atom to the C(6) atom, probably through involvement of a homoallyl cation. The resulting 6β-iodomethyl-16α,17α-cyclohexano-19-norpregn-5(10)-en-3β-ol (5) was transformed in three steps into 6α-methyl-16α,17α-cyclohexano-19-norprogesterone (6α-methyl-19-nor-D′ ₆-pentarane,8). The transformation of compound5 into the target product8 also gave a side product, a pentarane with aromatic ringA (10), which was isolated and characterized by spectroscopic methods. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1688–1691, September, 1997.     

Glutinane triterpenes from the stem bark of <Emphasis Type="Italic">Euonymus hamiltonianus</Emphasis>

Three new glutinane-type triterpenes, 19α-glutin-5-en-19-ol (1), 2β,15α,21β-glutin-11-ene-2,15,21-triol (2), and 2β,19α-glutin-7,21-diene-2,19-diol (3), were isolated from the stem bark of Euonymus hamiltonianus. Their structures were determined by 1D and 2D NMR along with MS and IR. Published in Khimiya Prirodnykh Soedinenii, No. 3, pp. 321–323, May–June, 2009.     

A new isocoumarin from mangrove endophytic fungus (No. dz17) on the South China Sea coast

A new isocoumarin, 3,4-dihydro-6-methoxy-8-hydroxy-3,4,5-trimethylisocoumarin-7-carboxylic acid methyl ester (1), together with three known compounds, 3,4-dihydro-4,8-dihydroxy-3,5-dimethylisocoumarin (2), 3,4-dihydro-8-hydroxy-3-methylisocoumarin-5-carboxylic acid (3), and Entinclole SB (4) were isolated from the mangrove endophytic fungus (No. dz17). The structure of the compound 1 was elucidated by analysis of spectroscopic data. Primary bioassays showed that 1 exhibited weak cytotoxicity against Hep-2 and HepG2 cells. Published in Khimiya Prirodnykh Soedinenii, No. 6, pp. 543–545, November–December, 2007.     

Ellagic acid derivatives from the stem bark of <Emphasis Type="Italic">Dipentodon sinicus</Emphasis>

Ellagic acid derivatives were isolated from Dipentodon sinicus and their structures were identified as 3,3′,4′-tri-O-methylellagic acid (1), 3,3′-di-O-methylellagic acid (2), 4,4′-di-O-methylellagic acid (3), 3,3′-di-O-methylellagic acid-4′-O-α-L-rhamnopyranoside (4), 3,3′,4′-tri-O-methylellagic acid-4′-O-β-D-glucopyranoside (5), 3,3′-di-O-methylellagic acid-4′-O-β-D-glucopyranoside (6), and ellagic acid (7). All the compounds were isolated for the first time from the title plant. Published in Khimiya Prirodnykh Soedinenii, No. 2, pp. 106–107, March–April, 2007.     

Chemical Constituents of Brown Rice Grain (<Emphasis Type="Italic">Oryza sativa</Emphasis>)

One new compound 3,7,11,15,19-pentamethyl-9α,10α,11α,17α,18α-pentahydroxy-n-tetracosan-1-oxy-p-hydroxycaffeoate (oryzaterpenyl caffeoate) (1), together with three known fatty acids linoleic acid, stearic acid and myristic acid were isolated and identified from the rice grain of Oryza sativa. The structure of the new compound was elucidated by 1D and 2D NMR spectroscopic techniques (¹H-¹HCOSY, ¹H-¹³C HETCOR) aided by EI-MS, and IR spectra. __________ Published in Khimiya Prirodnykh Soedinenii, No. 6, pp. 535–537, November–December, 2005.     

Synthesis of Derivatives of ω-Isocyanato-α-methylamino, ω-Ureido-α-methylamino,and N<Superscript>α</Superscript>-Methyl-α, ω-diamino Acids

Summary.  Homochiral N^α-methyl-2,3-diaminopropionic and N^α-methyl-2,4-diaminobutyric acid derivatives 8a,b were obtained via a stereoconservative four-step synthesis starting from hexafluoroacetone protected L-aspartic and L-glutamic acid 2a,b, respectively. Hexafluoroacetone protected ω-isocyanato-α-methylamino acids 4a,b– the key intermediates of the synthesis – are versatile building blocks for amino acid and peptide modification and promising candidates for combinatorial chemistry. Upon reaction with alcohols, compounds 4 give activated N ^ω-urethane protected ω-amino-α-methylamino acid derivatives 5–7; upon reaction with amines, ω-ureido-α-methylamino acid derivatives 10–12 and 3-methylamino-pyrrolidin-2-ones 13 are available. Received November 17, 1999. Accepted November 26, 1999     

Ellagic acid glycosides from the stem bark of <Emphasis Type="Italic">Aphananthe aspera</Emphasis>

Five ellagic acid glycosides were isolated from Aphananthe aspera and their structures were identified as 3-O-methylellagic acid-4′-O-α-L-rhamnopyranoside (1), 3-O-methylellagic acid-4′-O-β-D-xylopyranoside (2), 3,3′-di-O-methylellagic acid-4′-O-β-D-xylopyranoside (3), 3,3′, 4-tri-O-methylellagic acid-4′-O-β-D-glucopyranoside (4), and 3,3′-di-O-methylellagic acid-4′-O-α-L-rhamnopyranoside (5) on the basis of spectroscopic analysis. Compound 1 is new, and all the compounds were isolated for the first time from the title plant. Published in Khimiya Prirodnykh Soedinenii, No. 5, pp. 458–459, September–October, 2007.     

10-chloro-19-norcardiosteroids

Substitution of the angular aldehyde by halogen in cardiosteroids in two steps was studied. The first step was oxidation of the aldehyde and production of the cooresponding 19-carboxylic acids; the second, decarboxylation of the 19-carboxylic acids using N-chlorosuccinimide or chloride salts. The 10-chloro-19norcardiosteroids: 10-chloro-19-norstrophanthidine (1), 10-chloro-19-norcymarin (2), 10-chloro-19norconvallatoxin (3), 10-chloro-19-norstrophalloside (4), and 10-chloro-19-norbovoside A (5) were prepared for the first time. The intermediates strophalloside-19-carboxylic acid and bovoside A-19-carboxylic acid were also prepared for the first time and characterized.     

Five unusual natural carbohydrates from <Emphasis Type="Italic">Actinosynnema pretiosum</Emphasis>

Five unusual hexose derivatives were isolated from the carbohydrate portion of the solid-state fermentation extract of Actinosynnema pretiosum ssp. auranticum ATCC 31565, which is a producing strain of maytansinoids that are a family of 19-membered macrocyclic lactams having extraordinary cytotoxic and antineoplastic activities. Their structures were determined to be 2-deoxy-α-D-arabino-hexopyranose (1), 2-deoxy-β-D-arabino-hexopyranose (2), 3,6-anhydro-2-deoxy-α-D-arabino-hexcofuranose (3), 3,6-anhydro-2-deoxy-β-D-arabino-hexofuranose (4), and 2-(D-glycerol-1,2-dihydroxyethyl)furan (5) by NMR spectroscopic experiments. Published in Khimiya Prirodnykh Soedinenii, No. 5, pp. 481–483, September-October, 2008.     

Triterpene Glycosides from <Emphasis Type="Italic">Cussonia paniculata</Emphasis>. II. Acetylated Glycosides from Leaves

Structures of 13 new acetylated triterpene glycosides from leaves of Cussonia paniculata (Araliaceae) were established as 28-O-(2-O-acetyl- and 3-O-acetyl-α-L-rhamnopyranosyl)-(1→4)-O-β-D-glucopyranosyl-(1→6)-O-β -D-glucopyranosides of 23-hydroxybetulinic acid (1a and 1b) and hederagenin (2a and 2b), 3-O-α-L-arabinopyranosyl-28-O-(2-O-acetyl- and 3-O-acetyl-a-L-rhamnopyranosyl)-(1→ 4)-O-β-D-glucopyranosyl-(1→6)-O-β-D-glycopyranosides of oleanic (3a and 3b) and ursolic (3c and 3d) acids, 3-O-α-L-arabinopyranosyl-28-O-(4-O-acetyl-, 2-O-acetyl-, and 3-O-acetyl-α-L-rhamnopyranosyl)-(1→4)-O-β-D-glucopyranosyl-(1→ 6)-O-β-D-glucopyranosides of hederagenin (4, d5a and 5b), and 3-O-β-D-glucopyranosyl-(1→2)-O-α-L-arabinopyranosyl-28-O-(2-O-acetyl- and 3-O-acetyl-α-L-rhamnopyranosyl)-(1→4)-O-β-D-glucopyranosyl-(1→6)-O-β-D- glucopyranosides of oleanic acid (6a and 6b). The structures of the compounds were established using chemical methods and NMR spectroscopy. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 351–356, July–August, 2005.     

Synthesis of Derivatives of ω-Isocyanato-α-methylamino, ω-Ureido-α-methylamino, and Nα-Methyl-α, ω-diamino Acids

 Homochiral N^α-methyl-2,3-diaminopropionic and N^α-methyl-2,4-diaminobutyric acid derivatives 8a,b were obtained via a stereoconservative four-step synthesis starting from hexafluoroacetone protected L-aspartic and L-glutamic acid 2a,b, respectively. Hexafluoroacetone protected ω-isocyanato-α-methylamino acids 4a,b– the key intermediates of the synthesis – are versatile building blocks for amino acid and peptide modification and promising candidates for combinatorial chemistry. Upon reaction with alcohols, compounds 4 give activated N ^ω-urethane protected ω-amino-α-methylamino acid derivatives 5–7; upon reaction with amines, ω-ureido-α-methylamino acid derivatives 10–12 and 3-methylamino-pyrrolidin-2-ones 13 are available.     

Furofuran lignans from the bark of <Emphasis Type="Italic">Magnolia kobus</Emphasis>

A new furofuran lignan (1) along with four knownones (2-5) were isolated from the bark of Magnolia kobus. Their structures were elucidated as (+)-2α-(3’,4’-dimethoxyphenyl)-6α-(3″-hydroxy-4″,5″-dimethoxyphenyl)-3,7-dioxabicyclo[3.3.0]octane (1), (+)-sesamin (2), (+)-yangambin (3), (+)-kobusin (4), and (+)-eudesmin (5) on the basis of their comprehensive spectroscopic analysis, including 2D NMR, and by comparison of their spectral data with those of related compounds. Published in Khimiya Prirodnykh Soedinenii, No. 4, pp. 338–341, July–August, 2008.     

Three antibacterial compounds from the roots of <Emphasis Type="Italic">Pteris multifida</Emphasis>

A new eudesmane-type sesquiterpenoid, 3β-caffeoxyl-1β,8α-dihydroxyeudesm-4(15)-ene (1), together with two known compounds including ludongnin V (2) and isoneorautenol (3), were isolated from the roots of Pteris multifida. Their structures were determined by spectral and chemical methods, with their antibacterial activities being evaluated by the microdilution technique, respectively. Published in Khimiya Prirodnykh Soedinenii, No. 1, pp. 41–43, January–February, 2009.     

A new alkaloid from Lysimachia patungensis

A new pyridine alkaloid and six known compounds were isolated from the whole plant of Lysimachia patungensis Hand.-Mazz. The structure of the new alkaloid, named patungensin, was characterized as (17R, E)-2-hydroxy-4,6-dimethoxy-17-acetoxy-cyclopentadeca-1, 3-diene[1,2-b]pyridine, and the six known compounds were identified as octacosanoic acid (1), palmic acid (2), stigmasterol (3), ardisiacrispin A (5), isorhamnetin 3-β-D-galactopyranoside (6), and isorhamnetin 3-robinobioside (7), respectively. Published in Khimiya Prirodnykh Soedinenii, No. 2, pp. 141–142, March–April, 2007.     

Design and Synthesis of New Chiral Calix[4]arenes as Liquid Phase Extraction Agents for α-Amino Acid Methylesters and Chiral α-Amines

The article describes the synthesis and extraction properties of new (S)-(-)-1-phenylethylamine substituted p-tert-butylcalix[4]arene/calix[4]arene. These compounds have been synthesized via nucleophilic substitution reactions involving 5,11,17,23-tetra-tert-butyl-25,26,27,28-tetra(2-hydroxyethoxy)calix[4]arene (4a), or 5,11,17,23-tetra-H-25,26,27,28-tetra(2-hydroxyethoxy)calix[4]arene (4b) with (S)-(-)-1-phenylethylamine in dry THF. The extraction properties of ligands 5a and 5b towards the some selected α-amino acid methylesters and chiral α-amines are also reported. It has been observed that receptor 5a was an excellent ionophore for α-amino acid methylesters/α-amines and good extractant than 5b. However, both of the ligands did not display any selectivity towards the configurations of this species. in final form: 17 January 2005     

A new flavonol derivative from <Emphasis Type="Italic">Fagopyrum dibotrys</Emphasis>

A new flavonol derivative 3, 8-dihydroxy-10-methoxy-5-H-isochromeno[4, 3-b]chromen-7-one (1) together with four known compounds, glutinone (2), luteolin (3), acacetin 7-O-α-L-rhamnopyranosyl- (1→6)-β-D-glucopyranoside (4), and rutin (5) were isolated from the dried roots of Fagopyrum dibotrys. Their structures were determined by UV, IR, MS, ¹H, and ¹³C NMR spectroscopic analysis, including 2D NMR. Published in Khimiya Prirodnykh Soedinenii, No. 6, pp. 567–568, November–December, 2008.     

Chemical constituents from the roots of <Emphasis Type="Italic">Senecio scandens</Emphasis>

The chemical constituents of the roots of Senecio scandens Buch.-Ham. grown in the Funiu mountains in China have been investigated. Four compounds were isolated and identified as β−sitosterol (1), pentacosanoic acid (2), 19α-H lupeone (3), and sucrose (4). The structures of these compounds were elucidated on the basis of chemical and spectroscopic evidence. 19α-H Lupeone (3) was isolated as a single compound and its structure established unambiguously by the spectral method for the first time, and ¹H and ¹³C NMR data were assigned wholly by 1D and 2D NMR.     

Two novel phenolic compounds from <Emphasis Type="Italic">Stenoloma chusanum</Emphasis> and their antifungal activity

Two new phenolic compounds, 4-O-β-D-(6-O-gentisoylglucopyranosyl) vanillic acid (1), 2-O-β-D-(6-O-gentisoylglucopyranosyl) gentisic acid (2), together with three known compounds, vanillic acid (3), syringic acid (4), and gentisic acid (5), were isolated from the whole part of Stenoloma chusanum (L.) Ching. Structures of the two new compounds 1, 2 were elucidated on the basis of spectroscopic methods, including twodimensional NMR techniques and HR ESI-MS analysis. The compounds′ activities against Candida albicans, Cryptococcus neoformans, Trichophyton rubrum, Trichophyton mentagrophytes, Microsporum canis, Epidermophyton floccosum, and Aspergillus niger were determined, and the minimal inhibitory concentrations (MIC) were 25–100 μg/mL. Published in Khimiya Prirodnykh Soedinenii, No. 2, pp. 161–164, March–April, 2009.     

A furostanol saponin and phytoecdysteroid from roots of <Emphasis Type="Italic">Helleborus orientalis</Emphasis>

A furostanol saponin mixture and a known phytoecdysteroid were isolated from the roots of Helleborus orientalis Lam. Their structures were established as 26-[(β-D-glucopyranosyl)oxy]-22α-hidroxyfurosta-5,25(27)-dien-1β,3β,11α-triol (1a), 26-[(β-D-glucopyranosyl)oxy]-22α-methoxyfurosta-5,25(27)-dien-1β,3β,11α-triol (1b), and 20-hydroxy-β-ecdyson-3-O-β-D-glycoside (2). Acid hydrolysis of 1a,b gave (1β,3β,11α,22α)-22,26-dimethoxyfurosta-5,25(27)-dien-1,3,11-triol (aglycone 1) and of 2 gave 20-hydroxy-β-ecdyson (aglycone 2). Their structures were elucidated by spectral analysis. Published in Khimiya Prirodnykh Soedinenii, No. 1, pp. 75–77, January–February, 2007.