Showing papers by "Peyman Salehi published in 2013"

-Glucosidase and -amylase inhibitory effect and antioxidant activity of ten plant extracts traditionally used in Iran for diabetes

Abstract: In the present study various extracts of ten medicinal plants, collected in Iran, were examined for α-glucosidase and α-amylase inhibition using an in vitro model. Also total phenol content and antioxidant activity of the extracts were investigated. Various extracts of the plants (Cinnamomum zeylanicum, Crataegus oxyacantha, Hibiscus sabdariffa, Morus alba, Portulaca oleracea, Rubus fruticosus, Syzygium aromaticum, Teucrium polium,Trigonella foenum-graecum, and Vaccinium arctostaphylos) were prepared using n-hexane, dichloromethane, chloroform, ethyl acetate and methanol. Methanol, dichloromethane and n-hexane extracts of S. aromaticum exerted high in vitro inhibitory potential against α-glucosidase and α-amylase with IC50 ranging from 0.3 to 1.1 and 36.2 to 41.9 µg/ml, respectively. The mentioned extracts possessed the highest total phenolic contents (139.8, 119.6 and 136.1 mg GAE/g of extract). The antioxidant activities of the extracts, measured in terms of IC50 values were 2.2, 3.9 and 0.7 µg/ml, respectively. C. zeylanicum was another traditionally used medicinal plant, which its extracts exhibited high hypoglycaemic effect by inhibition of α-glucosidase and α-amylase (IC50 ranged from 0.5 to 8.7 and 37.1 to 52.5 µg/ml, respectively). The obtained results support the traditionally use of a number of the analyzed species. Key words: α-Glucosidase, α-amylase, enzyme inhibition, diabetes, antioxidant activity.

Antitrypanosomal triterpenoid with an ε-lactone E-ring from Salvia urmiensis.

Abstract: A new triterpenoid, urmiensolide (1), was isolated from Salvia urmiensis. The structure was elucidated by a combination of 1D and 2D NMR, HRESIMS, and X-ray crystallographic analyses. The absolute configuration was established by comparison of experimental and simulated ECD spectra. Urmiensolide is the first pentacyclic triterpenoid bearing a e-lactone E-ring. The compound showed in vitro antitrypanosoal activity with an IC50 value of 5.6 μM against the Trypanosoma brucei rhodesiense STIB 900 strain and a selectivity index of 33. A possible biosynthetic pathway of 1 from α-amyrin is proposed.

Antitrypanosomal isothiocyanate and thiocarbamate glycosides from Moringa peregrina.

Abstract: O-Methyl (1), O-ethyl (2), and O-butyl (3) 4-[(α-L-rhamnosyloxy) benzyl] thiocarbamate (E), along with 4-(α-L-rhamnosyloxy) benzyl isothiocyanate (4) have been isolated from the aerial parts of Moringa peregrina. The compounds were tested for in vitro activity against Trypanosoma brucei rhodesiense and cytotoxicity in rat skeletal myoblasts (L6 cells). The most potent compound was 4 with an IC50 of 0.10 µM against T.b. rhodesiense and a selectivity index of 73, while the thiocarbamate glycosides 1, 2, and 3 showed only moderate activity. Intraperitoneal administration of 50 mg/kg body weight/day of 4 in the T.b. rhodesiense STIB 900 acute mouse model revealed significant in vivo toxicity. Administration of 10 mg/kg body weight/day resulted in a 95% reduction of parasitemia on day 7 postinfection, but did not cure the animals. Because of its high in vitro activity and its ability to irreversibly inhibit trypanothione reductase, an attractive parasite-specific target enzyme, 4-[(α-L-rhamnosyloxy) benzyl] isothiocyanate (4), can be considered as a lead structure for the development and characterization of novel antitrypanosomal drugs.

Essential Oil Composition and Antioxidant Activity of Salvia staminea Benth. Extracts

Abstract: Essential oil composition and antioxidant activity of various extracts of Salvia staminea Benth. from Iran were investigated. Essential oil of S. staminea was isolated by hydrodistillation and characterized by GC and GC-MS methods. Thirty two compounds representing 93.3 % of the oil were identified. The major components were germacrene D (36.3 %) followed by hexahydrofarnesylacetone (11.2 %) and α-copaene (7.0 %). Various extracts of root and aerial parts of S. staminea were screened for their antioxidant properties using 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP) and ABTS assays. The level of rosmarinic acid content in the root and aerial parts extracts of S. staminea was determined by HPTLC method. The amount of rosmarinic acid in the root (0.42 mg/g) was more than two folds of its amount in the aerial parts (0.20 mg/g).

Efficient One-Pot, Four-Component Synthesis of 1,2,3-Triazole-Linked Tetrahydrobenzo[b]pyrans.

Abstract: A one-pot procedure has been developed for the synthesis of (1,2,3-triazolyl) methoxyphenyl tetrahydro-5-oxo-4H-chromene derivatives by concurrent reaction of aryloxy propargylated aldehydes, various azides, active methylene compounds, and 1,3-cyclohexanediones using catalytic amounts of Cu(OAc)2 / sodium ascorbate and diammonium hydrogen phosphate in aqueous ethanol media. Excellent conversion of starting materials was achieved to the desired (1,2,3-triazolyl) methoxyphenyl tetrahydro-5-oxo-4H-chromene products.

Facile and Highly Efficient Procedure for the Synthesis of Triazolyl Methoxyphenyl 1,8‐Dioxo‐decahydroacridines via One‐Pot, Pseudo‐Five‐Component Reaction.

Abstract: A series of triazolyl methoxyphenyl 1,8-dioxo-decahydroacridine derivatives has been prepared in a one-pot, pseudo-five-component reaction of aromatic propargylated aldehydes, various azides, dimedone, and a variety of amines in the presence of Cu(OAc)2/sodium ascorbate and 1-methylimidazolium trifluoroacetate ([Hmim]TFA) as the catalyst in good yields.