BackgroundThe fruit of Elaeagnus umbellata has high medicinal values and is an excellent source of phytochemicals. This study was aimed to evaluate the antioxidant, enzyme inhibitory and antidiabetic potential of Elaeagnus umbellata.MethodsThe antioxidant potential of the crude extract and subfractions of E. umbellata fruit were determined using DPPH (2, 20-diphenyl-1-picrylhydrazyl) and ABTS (2, 2′-azinobis-3-ethylbenzothiazoline-6-sulfonic acid) assays. The enzyme inhibitory potentials of extracts against α-amylase and α-glucosidase enzymes were also determined. The in vivo anti-hyperglycemic effects of the extract in STZ-induced type 2 diabetes were determined using Sprague Dawley adult rats. HPLC system (Agilent 1260) was used for the identification of bioactive compounds present in extracts. Molecular docking was used to identify and compare the interaction between the compounds (active constituents) and standard inhibitor acarbose with the α-amylase and α-glucosidase active sites.ResultsThe chloroform, ethyl acetate, and butanol fractions showed significant antioxidant potential with IC50 values of 40, 45 and 60 μg/mL against DPPH and 57, 70 and 120 μg/mL against ABTS free radicals respectively. The chloroform and ethyl acetate were highly active against α-amylase and α-glucosidase (IC50 values 58 and 200 μg/ml against α-amylase 60 and 140 μg/ml against α-glucosidase. The crude extract, chloroform, and ethyl acetate fractions were more potent in controlling the hyperglycemia in STZ-induced type 2 diabetes in rats and considerable reduction of glucose level was observed compared to the non-treated group. Furthermore, the extracts were also found useful in controlling the secondary complications associated with type 2 diabetes mellitus which was evident from the observed substantial reduction in the blood level of serum glutamate oxaloacetate transaminase, serum glutamate pyruvate transaminase, alkaline phosphatase, total cholesterol, low-density lipoproteins, and triglycerides. The molecular docking approach indicated the favorable inhibitory interaction between the docked compounds and the active sites of the α-amylase and α-glucosidase. All docked compounds occupied the same binding site as occupied by acarbose.ConclusionIt was concluded that E. umbellata can be used in the treatment of type 2 diabetes and oxidative stress. The extracts were also found to be effective in relieving the secondary complications associated with type 2 diabetes.Graphical abstract Electronic supplementary materialThe online version of this article (10.1186/s12906-018-2381-8) contains supplementary material, which is available to authorized users.

No abstract

No abstract

No abstract

Decarboxylation-allylation of allylic /3-keto carboxylates using Pd(OAc)2-PPh3 or Pd2(dba)3-CHCl3-dppe as a catalyst proceeds smoothly to give -allylated ketones. The reaction is highly regioselective. In some cases, diallylated ketones are obtained with allylic esters bearing an active proton(s). Also rhodium, molybdenum, and nickel complexes are active catalysts in this reaction. Similarly allylic esters of «-substituted malonates, cyanoacetates, and nitroacetate undergo the palladium-catalyzed decarboxylation-allylation to afford allylated acetate, acetonitrile, and nitromethane, respectively. The mechanisms of these palladium-catalyzed decarboxylation-allylations are discussed.

3-Keto esters are important intermediates used for regioselective alkylation of ketones. After their regioselective mono-or dialkylation, mono-or dialkyl ketones are derived by hydrolysis and subsequent decarboxylation. However,

SUMMARYAbstract:. An easy technique for introduction of tritium into the I-position of sphingosine was developed, employing regiospecific oxidation of the primary hydroxy group followed by reduction with NaB3H,. An improved preparation of t4,Bdimethylsphingosine and its quatemization are also described.

Background Elaeagnus umbellata is abundantly found in Himalayan regions of Pakistan which is traditionally used to treat various health disorders. However, the experimental evidence supporting the anti-amnesic effect is limited. Therefore the study was aimed to evaluate the prospective beneficial effect of E. umbellata on learning and memory in mice. Objectives To assess neuroprotective and anti-amnesic effects of E. umbellata fruit extracts and isolated compounds on the central nervous system. Methods Major phytochemical groups present in methanolic extract of E. umbellata were qualitatively determined. The total phenolic and flavonoid contents were also determined in extract/fractions of E. umbellata. On the basis of in vitro promising anticholinesterases (AChE & BChE) and antioxidant activities observed for CHF. Ext and isolated compound-I (Chlorogenic acid = CGA), they were further evaluated for learning and memory in normal and scopolamine-induced cognitive impairment in mice using memory behavioral tests such as the Y maze and Novel object recognition using standard procedures. The test sample were further assessed for in vivo anticholinesterases (AChE & BChE) and DPPH free radical scavenging activities in mice brain sample and finally validated by molecular docking study using GOLD software. Results The extract/fractions and isolated compounds were tested for their anticholinesterase and antioxidant potentials. The CHF. Ext and CGA showed maximum % inhibition of tested cholinesterases and free radicals. The CHF. Ext and CGA reversed the effects of scopolamine in mice. The CHF. Ext and CGA significantly increased the alternate arm returns and % spontaneous alteration performance while escape latency times (second) significantly decreased in Y maze test. The CHF. Ext and CGA significantly increased the time spent with novel object and also increased the discrimination index in the Novel object recognition test. Furthermore, molecular docking was used to validate the mechanism of cholinesterases inhibition of isolated compounds. Conclusion The data obtained from behavioral and biochemical studies (AChE/BChE and DPPH/ABTS inhibition) have shown that E. umbellata possessed significant memory enhancing potency. These results suggest that E. umbellata extract possess potential antiamnesic effects and amongst the isolated compounds, compound I could be more effective anti-amnesic therapeutics. However, further studies are needed to identify the exact mechanism of action. Graphical abstract