6-Methylcryptoacetalide, 6-methyl-epicryptoacetalide and 6-methylcryptotanshinone from Salvia aegyptiaca

From the whole plant of Salvia aegyptiaca, 6-methylcryptoacetalide, 6-methyl-epicryptoacetalide and 6-methylcryptotanshinone have been isolated and characterized, mainly by spectroscopic means. In addition to these novel diterpenoids, the known compounds 3beta-hydroxy-olean-12-en-28-oic acid, 3beta-hydroxy-oleana-11,13(18)-dien-28-oic acid, sitosterol-3beta-glucoside, sitosterol, stigmasterol, 5-hydroxy-7,3',4'-trimethoxyflavone and 5, 6-dihydroxy-7,3',4'-trimethoxyflavone were isolated.     

6-Hydroxyflavones from Thymbra spicata

Four flavonoids, including two new compounds, were isolated from the leaf extract of Thymbra spicata. The new compounds were the 7,3′-dimethyl and 7,3′,4′-trimethyl ethers of 6-hydroxyluteolin. All the compounds were identified by spectral methods.     

6-C-Glucosylnaringenin from Tulipa gesneriana

6-C-glucosylnaringenin, the first flavanone derivative found in Liliaceae, was isolated from the perianths of Tulipa gesneriana cv ‘Paradae’.     

6a-hydroxypterocarpans from red clover

Pisatin and homopisatin have been identified as antifungal compounds in red clover infected with either Botrytis cinerea, a non-pathogen, or Sclerotinia trifoliorum a clover pathogen. In addition 6a- hydroxymaackiain and 6a-hydroxymedicarpin have been detected. In vitro experiments have established that Sclerotinia can convert both maackiain and medicarpin to their respective 6a-hydroxylated products.     

Formation of 6 beta-hydroxydexamethasone from dexamethasone by A6 cells.

A6 cells, a continuous cell line derived from kidney of Xenopus laevis, were incubated with [3H]-dexamethasone for 24 h. When radioactive compounds in media were separated by reversed phase high pressure liquid chromatography, two radioactive fractions were found. The less polar fraction which contained 91-93% of total radioactivity cochromatographed with dexamethasone, whereas the polar fraction contained 5% of total radioactivity in media. In order to rigorously identify the polar metabolite, large scale cultures were carried out and the polar compound was separated and purified by reversed phase high pressure liquid chromatography. The purified material was analyzed by secondary ion mass spectrometry and nuclear magnetic resonance spectroscopy. By these procedures, this material was identified as 6 beta-hydroxydexamethasone. To our knowledge these are the first data indicating that dexamethasone can be metabolized by transporting epithelia such as A6 cells.     

Site-specific endonuclease BstM6I from Bacillus stearothermophilus M6]

A site-specific endonuclease activity was found in extract of Bacillus stearothermophilus M6 isolated from molasses. The functionally pure enzyme designated as BstM6I was obtained by consecutive chromatographies on blue sepharose, hydroxyapatite, and heparin-sepharose. The endonuclease recognizes the nucleotide sequence CC decreases WGG in double-stranded DNA and cleaves it as indicated by the arrow to give one-nucleotide 5'-protruding ends. Consequently, the site-specific endonuclease BstM6I is an isoshizomer of BstNI.     

Four 6-hydroxyflavonols from Blumea malcomii

Four new 6-hydroxyflavonols have been isolated from Blumea malcolmii and identified as 6-hydroxy-3,5,7,4′-tetramethoxyflavone, 6,2′,5′-trihydroxy-3,5,7-trimethoxyflavone, 6,5′-dihydroxy-3,5,7,2′-tetramethoxyflavone and 6-hydroxy-3,5,7,2′,5′-pentamethoxyflavone, by spectral data coupled with some chemical correlations.     

Sorbifolin 6-galactoside from Garcinia andamanica

A new flavone glycoside, sorbifolin 6-galactoside, has been isolated from the leaves of Garcinia andamanica along with the known scutellarein 7-diglucoside. Their structures were established using spectroscopic and chemical evidence.     

Isopullulanase from Arthrobacter globiformis T6

The physico-chemical properties of the purified glucose isomerases [d-xylose ketol isomerase, EC 5.3.1.5] of Streptomyces olivochromogenes and Bacillus stearothennophilus were examined. The molecular size and shape of both enzymes were similar. The molecular weights, sedimentation coefficients, partial specific volumes, diffusion constants and Stokes’ radii of the Streptomyces and Bacillus enzymes were determined to be 120,000 and 130,000, 7.55 S and 9.35 S, 0.725 and 0.736 ml/g, 5.87 × 10^-7 and 6.82 × 10^-7 cm²/sec, and 51 and 53 Å, respectively. The Streptomyces glucose isomerase was found to consist of two subunits, each having a molecular weight of 56,000. Large differences were found in the amino acid compositions of these two enzymes, especially in their serine, proline, tyrosine, lysine and arginine contents. The enzymatic properties of both these purified glucose isomerases were also examined, and it was seen that they both displayed activity on d-xylose, d-xylulose, d-glucose, d-fructose, d-arabinose and d-ribose. The smaller Km values and the larger molecular activities for d-xylose and d-xyluIose indicated that both enzymes are essentially d-xylose isomerases. The optimum temperature was 80°C for both enzymes. The optimum pH was 8 to 10 for the Streptomyces enzymes and 7.5 to 8.0 for the Bacillus enzyme. The Bacillus enzyme was more thermostable than the Streptomyces enzyme, but required cobalt ions in addition to magnesium ions for the full expression of its activity.     

Ungulates from Atapuerca TD6.

The ungulates from unit 6 of Gran Dolina (TD6) in the Sierra de Atapuerca (northern Spain) are studied. They include Stephanorhinus etruscus, Equus cf. altidens, Sus scrofa, Dama nestii? vallonetensis, Cervus elaphus, Eucladoceros giulii, Cervidae indet. and Bovini cf. "Bison voigtstedtensis." The taxonomy and stratigraphical distribution of most of these taxa are not universally accepted. S. etruscus, D. n.? vallonetensis, E. giulii and "B. voigtstedtensis" are late Early and early Middle Pleistocene elements. S. scrofa and C. elaphus range from the late Early Pleistocene to Recent. The fauna indicates a late Early or earliest Middle Pleistocene age, which fits the latest Early Pleistocene age suggested by palaeomagnetism. The faunal assemblage does not indicate extreme climatic conditions. The virtual absence of "glacial" taxa from the Spanish Early and Middle Pleistocene suggests that glaciations did not have a great impact on the fauna, suggesting that climate was no impediment to a continuous human occupation of Spain from the late Early Pleistocene onwards.     

Regioselective synthesis of 6-S-alkyl and 6-S-glycosyl-6-thio-D-mannofuranose derivatives from 5,6-O-cyclic sulfate precursors

C-6 opening of 5,6-cyclic sulfate derivatives of mannofuranose with a thiolate anion followed by acidic hydrolysis of the acyclic sulfate gave 6-S-alkyl derivatives in good yields (70-95%) and short reaction times (10-15min). This methodology was applied to the synthesis of methyl 2,3-O-isopropylidene-6-S-(2,3,4,6-tetra-O-acetyl-beta-d-glucopyranosyl)-6-thio-alpha-d-mannofuranoside (70%), 2,3-O-isopropylidene-6-S-(2,3,4,6-tetra-O-acetyl-beta-d-glucopyranosyl)-6-thio-alpha-d-mannofuranose (87%) and 2,3-O-isopropylidene-6-S-(1,2:3,4-di-O-isopropylidene-alpha-d-galactopyranos-6-yl)-6-thio-alpha-d-mannofuranose (87%).     

LignicolousHyphomycetes from Czechoslovakia 6.Spadicoides andDiplococcium

Seventeen species belonging toSpadicoides Hughes andDiplococcium Grove collected in Central Europe mostly in Czechoslovakia are described and illustrated. Two new species are described inSpadicoides—S. carpatica Hol.-Jech.,S. penatium Hol.-Jech. and three new species inDiplococcium—D. bicolor Hol.-Jech.,D. insolitum Hol.-Jech. andD. parcum,Hol.-Jech.     

6-Methoxyflavonoids from Brickellia californica

Two new and eleven known 6-methoxyflavonoids were identified in leaf tissue of Brickellia californica. The new flavonols are eupatin 3-SO₃ Ca_1/2 and patuletin 3-SO₃K. The known compounds include the flavones hispidulin and eupafolin and their respective 7- and 4′-monomethyl ethers and the flavonols; spinacetin, eupatin, patuletin 3-glucoside and 3-galactoside, and eupatolitin 3-galactoside.     

6-Methoxyflavonol 3-monosulphates from Flaveria chloraefolia

Flaveria chloraefolia leaves contain three novel 3-sulphates of 6-methoxykaempferol, spinacetin and eupalitin, together with the previously identified 3-sulphates of eupatolitin and eupatin. Purification of these compounds was carried out by gel filtration and chromatography of their tetrabutylammonium derivatives on polyamide and cellulose. Their structures were established by UV spectroscopy and negative FAB-MS of the tetrabutylammonium salts of the sulphate esters, as well as UV data and EI-MS of their aglycones.