Records of Natural Products Articles

Luteolin 6-rhamnosyl (1``` 4``) rhamnoside was isolated from Pteranthus dichotomus for the first time as a natural product along with eight compounds; kaempferol, quercetin, quercetin-7-glucoside, isoorientin, orientin-7-methoxide, luteolin, kaempferol-3-rhamnoside-7-glucouronic acid and myricetin-3-glucoside. The plant contained phenol, protocatechuic, p-hydroxy benzoic, gallic, p-coumaric and o-coumaric acids; they were identified by HPLC, the flavonoid compounds were purified by chromatographic methods, identified by chemical and physical methods including UV, 1H, 13C and 2D- NMR. The tested extract was highly safe as LD 50 (4 g/kg b.wt.), it has anti-inflammatory, moderate analgesic effect and caused increase in urine volume, it also had no effect on liver functions of animals. Kidney functions were impaired after large dose (100 mg/kg -1). It has Anti-tumor activity against Ehrlish Ascites Carcinoma. The new isolated compound showed antipyretic effect and increased the urine volume while the tested extract had moderate antipyretic activity in rats.

One new metabolite, prunol (1), belonging to the pentacyclic triterpenoid skeleton was purified from the dichloromethane soluble fraction of the crude ethanolic extract of Prunus cerasoides D. Don. The structure elucidation was accomplished on the basis of one dimensional 1H and 13C NMR and two dimensional HMQC, HMBC, and COSY experiments. The molecular mass was determined by HRFAB-MS, while the major fragments were observed in the EI-MS. The comparative analysis of the NMR spectral data with the known analogues and the NOESY experiments were helpful in assigning the stereo centers in the molecule.

Serratula L. (Astareceae) rich in ecdysteroid, phytoecdysteroids and flavonoids some have various biological activities including antibacterial and antitumor. The fatty acid profiles of four Serratula species were investigated by using GC and GC–MS techniques. Palmitic, oleic, linoleic and linolenic acids were found to be the main fatty acids. The unsaturation percentage was between 27.24-50.47%. The antioxidant activity of the extracts was determined by using four complementary tests; namely, β-carotene-linoleic acid, DPPH• scavenging, CUPRAC and ferrous-ions chelating assays. The methanol extract of S. lasiocephala showed the highest activity in β-carotene-linoleic acid, DPPH• scavenging and CUPRAC assays, while the hexane extract of S. radiataexhibited the best metal chelating activity. In addition, total phenolic and total flavonoid contents in the extracts were determined as pyrocatechol and quercetin equivalents, respectively. The in vitro anticholinesterase activity of extracts were tested against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) which are the key enzymes taking place in pathogenesis of Alzheimer’s disease. Besides, the extracts were tested in vitroagainst tyrosinase enzyme which is associated with melanin hyperpigmentation. Except the hexane extracts of S. radiata and S. lasiocephala, the extracts showed moderate inhibition against AChE and BChE, while the only hexane extract of S. erucifolia and methanol extract of S. radiata exhibited tyrosinase inhibitory activity.

To find new products reducing free radical damage is very important research area in recent pharmaceutical investigations. Considering this information, different marine sponges distributed in Mediterranean coasts of Turkey were screened for their antioxidant capacity. Methanolic extracts of eleven species from six different localities were investigated for their 2,2-diphenyl-1-picrylhydrazil (DPPH), nitric oxide (NO) and superoxide (SO) radical scavenging activities. Dose dependent radical scavenging activity was observed and the results were found to be comparable to that of known antioxidative compounds, ascorbic acid, quercetin and BHA. The most significant scavenging activity was determined for the methanolic extracts of Dysidea avara, Axinella cannabina, Axinella damicornis, Agelas oroides and Ircinia fasciculata. In addition, localities of the sponges were found to be effective for the potency of their activities.

In continuation of our chemical studies on the secondary metabolites of Algerian saharan species, we report on the isolation, from the methanol extract of the whole plant Astragalus cruciatus Link. , of seven known compounds including two saponins named azukisaponin V (1) and astragaloside VIII (2), four flavonoids called narcissin (3), nicotiflorin (4), kaempferol 3-O- α -L-rhamnopyranosyl-(1 ¦ 4)- α -L-rhamnopyranosyl-(1 ¦ 6)-β-D-glucopyranoside (5) and 5,7,2’-trihydroxyflavone (6) and one phytosterol glycoside, daucosterol (7). All the isolated compounds were characterized by using spectroscopic methods especially 1D and 2D NMR and ESI mass spectrometry and comparison with literature data . The chemotaxonomic and systematic characters of the genus Astragalus are summarized in this study to show its interesting chemodiversity throughout the world, as well as to establish the chemotaxonomical classification of this genus.

A new g -lactone named maroccanin (1) together with 5 known compounds : scopoletin (2); 8 a -[2’-hydroxymethyl-2’-butenoyloxy]-dehydromelitensin (3); 11,13-dehydromelitensin (4); 8 a -[2’-hydroxymethyl-2’-butenoyloxy]-sonchucarpolide (5) and 5Hα,6Hβ,7Hα,-15-hydroxy-8α-( 1’,2’-dihydroxyethyl-acryloxy)-elema-1(2),3(4),11(13)-trien-6,12-olide (6), were isolated from the chloroform soluble part of the aqueous-MeOH extract of the flowering aerial parts of C.maroccana Ball. (Asteraceae), an endemic species of the North of the Sahara. The structures were established by chemical and spectral analysis, mainly HR-ESIMS, HREIMS,UV and NMR experiments (COSY, NOESY, HSQC and HMBC). The compounds 3 and 5 are new for the genus Centaurea .

 Chemical investigation of the sponge Mycale species from the South China Sea afforded eleven known compounds, henicosanoic acid methyl ester (1) , hexadecyl ethers of glycerol ( 2 ) , N-docosanoyl-D-erythro-(2S,3R)-16-methyl-heptadecasphing-4(E)-enine ( 3 ) , dibutyl phthalate ( 4 ) , cholesterol ( 5 ) , 5α,8α-epidioxycholest-6,22-dien-3β-ol ( 6 ) , 5-hexadecyl-pyrrole-2-carboxaldehyde ( 7 ) , benzoic acid ( 8 ) , 4-hydroxybenzoic acid ( 9 ) , thymine ( 10 ) ,and uracil ( 11 ) . Compounds 1 – 4 , 6 – 9 were obtained from the sponge of the genus Mycale for the first time, and 4 and 6 showed toxicity in the brine shrimp lethality test with the LD 50 values at 2.9 μg/mL and 4. 7 μg/mL, respectively .

 A new cassane-type d iterpene, named Phangininoxy A (1) and one known Phanginin A (2) were isolated from the exact of seeds of Caesalpinia sappan Linn. Their structures were elucidated by spectroscopic methods, mainly 1D and 2D NMR.

A methanol extract prepared from the bark of Canarium subulatum Guillaumin (Burseraceae) showed significant anti-herpetic activity. Chemical investigation of this plant extract resulted in the isolation of nine compounds which included β -amyrin (1), (-)-cubebin (2), scopoletin (3), 3,4-dihydroxybenzoic acid (4), 3,3 ¢ -di-O-methylellagic acid-4 ¢ -O-α-L-rhamnopyranoside (5), 3,3 ¢ -di-O-methylellagic acid-4 ¢ -O-β-D-gluco-pyranoside (6), 3-O-methylellagic acid-4 ¢ -O-α-L-arabinofuranoside (7), scopolin (8) and 3-O-methylellagic acid-4 ¢ -O-β-D-xylopyranoside (9) . The structures of these compounds were determined mainly through analysis of 1H and 13C NMR and MS data. All of the isolates were evaluated for anti-herpetic and DPPH free radical scavenging properties. β -Amyrin (1) and ( - )-cubebin (2) showed moderate anti-herpetic activity, whereas 3,4-dihydroxybenzoic acid (4), 3,3 ¢ -di-O-methylellagic acid-4 ¢ -O-α-L-rhamnopyranoside (5) exhibited recognizable DPPH free radical scavenging potential. This study is the first report on the chemical and biological properties of C. subulatum.

A catecholate type of iron chelator (siderophore); 2,3-dihydroxybenzoyl glycine (DHBG) was produced by Bacillus sp. under i ron stress conditions. Pure DHBG was subjected for DPPH ( α,α−Diphenyl−β− Picrylhydrazyl ) radical scavenging activity and radical induced DNA cleavage inhibition assay. In results, DHBG showed the highest radical scavenging effect and DNA cleavage inhibition activity when it was free from iron. This study revealed antioxidative potential of iron chelator DHBG; and its probable mechanism.

Aspidosperma macrocarpon belongs to the family Apocynaceae and is endemic to Americas and mainly found from Mexico to Argentina. It is known in Brazil as “guatambu” or “peroba”. Crude extracts and their fractions from leaves were assayed against human cancer cells lines: glioma (U251), melanoma (UACC-62), mammary (MCF-7), ovarian expressing the multidrug resistance phenotype (NCI-ADR/RES), lung (NCI-H460), prostate (PC-3), kidney (786-0), ovarian (OVCAR-3), colon (HT-29) and leukemia (K-562). The crude extract (EAM), hexane (HA) and chloroform (CA) fractions were the most active fractions against K-562 with GI50 values low than 1 µg/mL. Also, CA was moderate active against OVCAR-3 and NCI-ADR/RES cells lines. This phytochemical study allowed to identify the known kopsanone, kopsinine, ursolic acid, rutin, 5-O-caffeoylquinic acid, and 3,5-O-dicaffeoylquinic acid. The kopsanone was also evaluated against human cancer cell lines and showed activity to the U251 and K-562 cell lines, with GI50 values of 20.6 µg/mL and 8.7 µg/mL, respectively.

Melicimides A (1) and B (2), two new ceremides have been isolated from Melicia excelsa ( Moraceae). The structures of the new compounds were determined by comprehensive analyses of their 1D ( 1H and 13C NMR), 2D NMR (including COSY, HMQC, and HMBC) and ESIMS spectral data. A known compound viz., β-sitosterol has also been identified.

The aim of the present study was to evaluate the acetylcholinesterase inhibitory capacity and the antioxidant properties of extracts of Euphorbia characias latex, a Mediterranean shrub. We performed a new extraction method involving the use of the trichloroacetic acid. The extract showed high antioxidant activity, was rich in total polyphenolic and flavonoid content and exhibited substantial inhibition of acetylcholinesterase activity.

LC-DAD-UV and LC-ESI-MS-based analyses were performed in order to chemically characterize a phenol-enriched fraction obtained from Iryanthera ulei leaves-derived ethanol extract. Eight glycosylated flavonoids, two free-flavonoids and two neolignans were detected to be part of its isopropyl acetate-soluble (iPS) fraction. Presence of afzelin 1 was confirmed by isolation. Total Phenolic (TPC) and Total Flavonoid Contents (TFC), Antioxidant Capacity (DPPH, ABTS • + , and FRAP methods), as well as antimicrobial activity against five strains were determined.

he first occurrence of a 3,4-seco-taraxerane triterpenoid in Mallotus species (Euphorbiaceae) is reported. The triterpenoid was isolated from the leaves of the Vietnamese medicinal plant Mallotus barbatus ( Wall.) Muell.-Arg. and its structure was determined to be 3,4-seco-taraxer-14-en-3-oic acid on the basis of HR-MS and NMR spectroscopic methods. For the first time, the 1 H and 13C NMR data and stereochemistry of this compound were fully established on the basis of the 1H- 1H COSY, NOESY, HSQC, and HMBC spectroscopic data.