A spectroscopic investigation of the phenolcarboxylic acids ofCynara scolymus

Summary Spectroscopic investigations in the UV region of the phenolcarboxylic acids that we have isolated from the leaves ofCynara scolymus have been carried out. It has been found that:1. Free caffeic acid can be distinguished from its esters by the changes in the UV spectra under the influence of sodium ethoxide and sodium acetate.2. An o-dihydroxy grouping in esters can be detected from the bathochromic shift observed with boric acid in the presence of sodium acetate.3. An o-dihydroxy grouping can be detected both in esters and in the free acid under the influence of aluminum chloride.Khimiya Prirodynkh Soedinenii, Vol. 2, No. 5, pp. 303–306, 1966     

A new flavonoid from the leaves of Atalantia monophylla (L.) DC

A new flavonoid, atalantraflavone (1) as well as eight known compounds including atalantoflavone (2), racemoflavone (3), 5,4′-dihydroxy-(3″,4″-dihydro-3″,4″-dihydroxy)-2″,2″-dimethylpyrano-(5″,6″:7,8)-flavone (4), lupalbigenin (5), anabellamide (6), citrusinine I (7), p-hydroxybenzaldehyde (8), and frideline (9), were isolated from the leaves of Atalantia monophylla (L.) DC. Focusing on Alzheimer’s disease, acetylcholine esterase (AChE) inhibition and antioxidant activity were evaluated using the modified Ellman’s method and the ABTS scavenging assay, respectively. It was found that isoflavonoid 5, lupalbigenin, showed 79% inhibition to AChE and was 1.4-fold stronger than the tacrine standard. In addition, acridone 7, citrusinine I, displayed 90.68% antioxidant activity.     

A new flavonoid from the bract of Zea mays L.

<正>A new flavonoid was isolated from the bract of Zea mays L.The structure of the compound was identified as 4',5,7-trihydroxy-3',5'-dimethoxyflavone 7-O-[β-D-apiofuranosyl(1→2)]-β-D-glucopyranoside on the ground of chemical and spectroscopic methods.     

Chemical investigation of the polysaccharides of the leaves ofPlantago major L.

Summary 1. A polysaccharide has been isolated from the leaves ofPlantage major L. and its monosaccharide composition has been studied.2. It has been established that the polysaccharide investigated contains D-galacturonic acid, D-galactose, D-glucose, D-xylose, L-rhamnose, L-arabinose, a partially methylated galactose, and two unidentified monosaccharides.3. The high content of galacturonic residues (68%) in the polysaccharide enables it to be classified as a pectin.Khimiya Prirodnykh Soedinenii, Vol. 1, No. 5, pp. 297–302, 1965     

Chemical investigation of the polysaccharides of the leaves ofPlantago major L.

Summary 1. Pectic acid contains galacturonic acid (78–83%) and, chemically linked with it, the monosaccharides D-galactose, L-arabinose, L-rhamnose, and substance (VIII) and (IX).2. By fractionating the polysaccharide complex of the leavesof Plantago major L. on a DEAE-cellulose column it has been shown that it consists of pectic acid (80–82%), and free galactoraban (5–6%) and galactan (4–5%).Khimiya Prirodnykh Soedinenii, Vol. 1, No. 6, pp. 369–372, 1965.We have used Kertesz's nomenclature of pectic compounds [4].     

A new acylated flavonoid tetraglycoside with anti-inflammatory activity from Tipuana tipu leaves

A new acylated kaempferol glycoside, kaempferol 3-O-α-l-rhamnopyranosyl-(1 → 6)-O-[β-d-glucopyranosyl-(1 → 2)-4-O-acetyl-α-l-rhamnopyranosyl-(1 → 2)]-β-d-galactopyranoside, has been isolated from the leaves of Tipuana tipu (Benth.) Lillo growing in Egypt, along with three known flavonol glycosides, kaempferol 3-O-rutinoside, quercetin 3-O-rutinoside (rutin) and kaempferol 3-O-[α-l-rhamnopyranosyl-(1 → 6)]-[α-l-rhamnopyranosyl-(1 → 2]-β-d-glucopyranoside. Structure elucidation was achieved through different spectroscopic methods. Structure relationship with anti-inflammatory activity using carrageenin-induced rat paw oedema model is discussed.     

A new benzophenone glycoside from the leaves of Psidium guajava L.

A new benzophenone glycoside,2,6-dihydroxy-4-O-β-D-glucopyranosylbenzophenone(1),was isolated from the leaves of guajava L.Its structure was elucidated by spectral and chemical methods.1 showed significant activities to secretion of NO in mouse peritoneal macrophages in 10μmol/L.     

A new benzofuran derivative from the leaves of Ficus pumila L.

A new benzofuran derivative, pumiloside (1), together with seven known flavonoid glycosides, afzelin (2), astragalin (3), quercitrin (4), isoquercitrin (5), kaempferol 3-O-rutinoside (6), rutin (7) and kaempferol 3-O-sophoroside (8) were isolated from the leaves of Ficus pumila. Their structures were established by spectroscopic data and comparison with the literature values.     

Protogenkwanin,a new flavonoid from equisetum arvense L

From the fertile sprouts of Equisetum arvense L. have been isolated protogenkwanin 4'-glucoside and gossypitrin. The structure of protogenkwanin as 5-hydroxy-2-(1,4-dlhydroxy-2,5-cyclohexadienyl)-7-methoxy-4-chromenon is proved on the basis of chemical and physical evidence. It is demonstrated that articulatin a thiamine decomposing substance, from E. arvense, is identical with the known flavonol glycoside gossypitrin (= gossypetin-7-glucoside). The synthesis of 2,5-dihydroxy-2-(4 hydroxyphenyl)-7-methoxy-4-chromanon is reported.