ANTI-HYPERGLYCEMIC EFFECT OF DIFFERENT FRACTIONS OF ANNONA RETICULATA LEAF

ABSTRACTContext: Several species of the genus Annona were reported to have hypoglycemic properties and this makes Annona reticulata Linn. (Annonaceae)an interesting plant for investigating its anti-hyperglycemic potential.Objective: Different fractions prepared from hydro-alcoholic extract of A. reticulata leave were investigated for their blood glucose lowering effect onStreptozotocin (STZ) induced hyperglycemic rats.Methods: Ethyl acetate, methanol, and residual fractions (at dose level of 100 mg/kg by oral route) prepared from the hydro-alcoholic extract ofA. reticulata leave were administered for 14 consecutive days to STZ induced hyperglycemic rats for evaluation of their anti-hyperglycemic potential.Anti-hyperglycemic potential was assessed by observation of a decrease in fasting blood glucose level.Results: The studies revealed that ethyl acetate fraction decreased the blood glucose level of hyperglycemic rats from 447.67 to 234.17 mg/dL and issignificant (p<0.001) when compared with diabetic control group. The residual fraction and methanolic fraction decreased blood glucose level from417.83 to 402.50 mg/dL and 432.33 to 371.67 mg/dL respectively but not significant when compared with the diabetic control group. Standard drugmetformin (dose 300 mg/kg) reduced the blood glucose level from 447.33 to 219.50 mg/dL.Discussion: Ethyl acetate fraction at tested dose level was capable not only to control the elevated blood glucose level but also able to attenuatecertain secondary parameters associated with STZ induced hyperglycemia.Conclusion: This study suggested that the ethyl acetate fraction prepared from hydro-alcoholic extract of A. reticulata leave exhibit potential antihyperglycemicpropertyin the testedexperimentalmodels and should be investigatedfurther.Keywords: Streptozotocin, Diabetes, Dyslipidemia

Silica-supported vanadium-catalyzedn-oxidation of tertiary amines with aqueous hydrogen peroxide

A recyclable silica supported vanadium 1 catalyzes the oxidation of tertiray amines to the corresponding N-oxides with 30% H<SUB>2</SUB>O<SUB>2</SUB> in high yield

Recent advances in copper-catalyzed oxidation of organic compounds

The copper-catalyzed oxidation of organic compounds has made considerable progress in the recent years. Molecular oxygen, aqueous hydrogen peroxide, tert-butyl hydroperoxide and peroxyesters have been employed as terminal oxidants for this purpose. The use of polymer and solid-supported catalysts, ionic liquids and fluorous biphase systems (FBS) has been demonstrated to facilitate the recyclability of the catalysts. Efforts have been made for the aqueous oxidation processes employing water-soluble copper complexes. Chiral catalysts have been designed and developed for the enantioselective oxidative coupling of 2-naphthols, Baeyer–Villiger oxidation and Kharasch–Sosnovsky reaction with high enantioselectivity

Vanadium-catalyzed selective oxidation of alcohols to aldehydes and ketones with tert-butyl hydroperoxide

The oxidation of alcohols to aldehydes and ketones has been described using silica-supported vanadium(IV) oxide (V/SiO<SUB>2</SUB>, 1) in the presence of tert-butyl hydroperoxide in tert-butyl alcohol at ambient temperature with quantitative yields. The procedure is simple, efficient and environmentally benign

Novel CuO nanoparticle catalyzed C−N cross coupling of amines with iodobenzene

CuO nanoparticles catalyze the C−N cross coupling of amines with iodobenzene in excellent yields. The reaction is simple and efficient and operates under air with ligand free conditions. The catalyst is recyclable without loss of activity

Efficient CuO-nanoparticle-catalyzed C-S cross-coupling of thiols with idobenzene

Attraktiv und preiswert: Leicht erhältliche CuO-Nanopartikel kosten nicht nur weniger als andere Katalysatoren für die C-S-Kreuzkupplung, sie sind überdies schon bei moderaten Temperaturen und geringen Konzentrationen aktiv. Die Titelreaktion führt mit zahlreichen Alkyl- und Arylthiolen in hohen Ausbeuten zu den entsprechenden Sulfiden (siehe Schema)

Chiral linear polymers bonded alternatively with salen and 1,4-dialkoxy-2,6-diethynylbenzene: synthesis and application to diethylzinc addition to aldehydes

The synthesis of chiral polymers 1 bonded alternatively with salen and 1,4-dialkoxy-2,6-diethynylbenzene was accomplished. These polymers are recyclable and catalyze the Et<SUB>2</SUB>Zn addition to aldehydes with good enantioselectivity

Synthesis, structure, and application of self-assembled copper(II) aqua complex by H-bonding for acceleration of the nitroaldol reaction on water

Copper(II) aqua complex 1 has been prepared in a one-pot synthesis. The single crystal X-ray analysis showed that the complex is self-assembled through aqua ligands by H-bond interactions and the copper(II) atoms are pentacoordinated with square pyramidal geometry. Complex 1 has been studied for the acceleration of the nitroalodol reaction on water. It is a clean technological process and the catalyst can be recycled without loss of activity. © 2009 Wiley-VCH Verlag GmbH & Co. KGaA

CuO nanoparticles catalyzed C−N, C−O, and C−S cross-coupling reactions: scope and mechanism

CuO nanoparticles have been studied for C−N, C−O, and C−S bond formations via cross-coupling reactions of nitrogen, oxygen, and sulfur nucleophiles with aryl halides. Amides, amines, imidazoles, phenols, alcohols and thiols undergo reactions with aryl iodides in the presence of a base such as KOH, Cs2CO3, and K2CO3 at moderate temperature. The procedure is simple, general, ligand-free, and efficient to afford the cross-coupled products in high yield

Isothermal Calorimetric Titrations on Charge-Assisted Halogen Bonds: Role of Entropy, Counterions, Solvent, and Temperature

We have conducted isothermal calorimetric titrations to investigate the halogen-bond strength of cationic bidentate halogen-bond donors toward halides, using bis­(iodoimidazolium) compounds as probes. These data are intended to aid the rational design of halogen-bond donors as well as the development of halogen-bond-based applications in solution. In all cases examined, the entropic contribution to the overall free energy of binding was found to be very important. The binding affinities showed little dependency on the weakly coordinating counteranions of the halogen-bond donors but became slightly stronger with higher temperatures. We also found a marked influence of different solvents on the interaction strength. The highest binding constant detected in this study was 3.3 × 10⁶ M^–1