Pumice as a Novel Nature Heterogeneous Catalyst for Synthesis of 3,4-dihydropyrimidine-2-(1H)-Ones/Thiones via Biginelli Reaction under Solvent-free Conditions

An efficient and environmentally Pumice as a new catalyst for designing of 3,4- dihydropyrimidin-2(1H) ones / thiones via one-pot multi component condensation of aromatic aldehydes, urea/ thiourea and ethyl acetoacetate or acetyl acetone in excellent yields (96-99 %). The advantages using of this new catalyst is very cheap, available, non-toxic, stable under thermal conditions, easy work-up, improved yields, the product of reaction is very pure without using chromatographic methods and solvent free conditions.

A NEWER METHODDEVELOPED FOR THE SYNTHESIS OF DIFERULOYL METHANE AND ITS DERIVATIVES

Here in the current research work we have developed newer method for the synthesis of diferuloyl methane(curcumin)Ca-q. MangnesiumHydroxide were found to be an effective and mild base for synthesis of curcumin and its derivatives obtained by reaction of one equivalent of acetyl acetone with two equivalent of corresponding aromatic aldehyde in microwave(240 W). The existingscheme offers severalaids such as high yield, less time, and environmentally friendly.

Orthoamide und Iminiumsalze, CI. Umsetzungen von N,N,N′,N′-Tetramethylharnstoffdiethylacetal mit CH2-aciden Verbindungen

N,N,N′,N′-Tetramethylurea diethylacetal reacts with CH2-acidic compounds as benzylcyanide, cyanoacetic acid derivatives malonodinitrile and nitromethane to give ketene aminals or ketene-O,N-acetales. Low polar solvents favour mostly the formation of ketenaminals. The yields of ketenaminals and ketene-O,N-acetals can be improved in some cases by addition of trimethylsilyldimethylamine. The reactions of the urea acetal with diethylmalonate, ore acetyl acetone, stops at the stage of the N,N′,N″-permethylated guanidinium salts with carbanionic counterions. The formation of bis(dimethylamino)methylene-diethylmalonate from the urea acetal and diethylmalonate can be initiated by addition of trimethylsilyldimethylamine/trimethylsilylcyanide. N,N,N′,N′,N″,N″-Hexamethylguanidinium cyanide is formed in the analogous reactions of the urea acetal with N,N-dimethylcyanacetamide or diethylsuccinate. The N,N′,N″-Hexamethyl-guanidinium nitrite can be obtained from the urea acetal and nitropropane.

Green Synthesis of Substituted dihydropyrimidin-2(1H)-one by using Zinc Chloride /acetic acid Catalytic System

Background: Biginelli reaction is the most well-known and widely studied multicomponent reaction used for the direct synthesis of many biologically active 3,4-dihydropyrimidin-2(1H)-ones and their derivatives by reacting a β-keto ester/1,3- dicarbonyl compound, an aldehyde, and urea. It was catalyzed by different Bronsted and Lewis acids. Methods: The catalytic effect of different metal chloride such as sodium, potassium, magnesium, stannous, ferric, manganese, cupric, nickel, cobalt, and zinc chlorides in absence and presence of acetic acid were studied. Results: The zinc, ferric, cupric, and cobalt chlorides were found to be more effective catalysts for Biginelli reaction at room temperature. The yield of reaction was increases with temperature for all catalytic system. Acetophenone, cyclohexanone, acetyl acetone, and different β-ketoesters forming tetrahedropyrimidine in moderate to good yield by using zinc chloride catalyst at room temperature in acetic acid. The efficiency of the catalyst was studied by treating different substituted aldehydes with 1,3-dicarbonyl compounds and urea at room temperature Results: The zinc, ferric, cupric, and cobalt chlorides were found to be more effective catalysts for Biginelli reaction at room temperature. The yield of reaction was increases with temperature for all catalytic system. Acetophenone, cyclohexanone, acetyl acetone, and different β-ketoesters forming tetrahedropyrimidine in moderate to good yield by using zinc chloride catalyst at room temperature in acetic acid. The efficiency of the catalyst was studied by treating different substituted aldehydes with 1,3-dicarbonyl compounds and urea at room temperature. Conclusion: The zinc chloride in acetic acid found to be effective greener catalyst system for Biginelli reaction.

Impact of Acetyl Acetone on Zinc Uptake and Oxidative Stress in Cucumber (Cucumis sativus)

The purpose of this research is to determine the impacts of acetyl acetone on zinc uptake and oxidative stress in cucumber (Cucumis sativus) seedlings grown in hydroponic solutions. Thirty seedlings of cucumber were collected from Kura local government area Kano, Kano state. Concentrations of Zn2+ in the hydroponics were varied from 0.000 to 0.025 mol dm-3 and of acetyl acetone were also varied from 0.000 to 0.025 mol dm-3. The seedlings were replanted and kept at Department of Agriculture Kano University of Science and Technology, Wudil garden. The weight of plants increased significantly (p<0.05) with concentration of Zn2+ in the absence of acetyl acetone and highly insignificantly (p>0.05) with concentration of acetyl acetone in the absence of Zn2+. In the presence of acetyl acetone and Zn2+ plant weight decreased highly insignificant (p>0.05). Leaf fall was observed from plants in all hydroponic, the number of falling leaves was insignificant (p>0.05) with concentration of Zn2+ but it is insignificant (p>0.05) with concentration of acetyl acetone and highly insignificant in the presence of acetyl acetone and Zn2+ (p>0.05). The volume of the solution decreased highly significant (p<0.05) with concentration of Zn2+ and significant with concentration of acetyl acetone (p<0.05) the volume also increased insignificantly in the presence of acetyl acetone and Zn2+ (p>0.05). The pH values of treated hydroponics before replanting and after harvest were insignificant with increased in the concentration of Zn2+ (p>0.05). Both shoot and root zinc accumulated were insignificant at lower concentration of Zn2+ (p>0.05) and significant at higher concentration of Zn2+ (p<0.05). The zinc translocation factor decreased highly insignificantly (p>0.05) at lower concentration of Zn2+ and significant at higher concentration of Zn2+ (p>0.05) in treated plants compared to control. The chlorophyll, carotenoid and proline content varied in the presence and absence of acetyl acetone and or combination of the two, with (p<0.05) or (p>0.05).

Effects of Acetyl Acetone on Growth and Zinc Uptake by Drumstick (Moringa Oleifera) Seedlings Replanted in Hydroponic Solutions

The aim of this work was to investigate the effects of acetyl acetone on Zinc (Zn) uptake and growth of Drumstick (Moringa oleifera) plants. Thirty seedlings were raised in hydroponic solution containing varied concentrations of Zn and acetyl acetone. The results showed a significant (p>0.05) change in weights of the plants when concentrations of Zn and acetyl acetone were added. Plants grown in treated hydroponics died before control plants. Zn uptake and accumulation were dose dependent with respect to addition of both Zn and acetyl acetone. The translocation factor decreased highly insignificantly (P>0.05) at lower concentration of Zn and significant at higher concentration in treated plants compared to control. The chlorophyll, carotenoid and proline content were severely decreased after addition of Zn and acetyl acetone, inducing toxicity symptoms. Thus, acetyl acetone did not play any significant role in alleviating Zn-induced toxicity.