An Efficient One-Pot Synthesis of Pyrazolopyrimidines, Intermediates for Potential Phosphodiesterase Inhibitors

Summary. A simple high-yielding procedure is presented for the synthesis of pyrazolopyrimidinones overcoming limitations found in earlier work and of considerable utility for the production of intermediates for potential phosphodiesterase inhibitors.     

由盐一锅法合成α-苯硫基-α,β-不饱和羰基化合物

在三乙胺存在下,(钅申)盐与苯硫基氯化物反应,然后与醛反应,产生相应的α-苯硫基-α,β-不饱和羰基化合物,构型以(Z)-型为主,产率良好.     

An Efficient, One-Pot, Triton-B Catalyzed Synthesis of O-Alkyl-S-methyl Dithiocarbonates

Summary. A novel process for the one-step conversion of a variety of primary and secondary alcohols into their O-alkyl-S-methyl dithiocarbonates using methyl iodide catalyzed by the Triton-B/CS₂ system was developed. Thus, O-alkyl-S-methyl dithiocarbonates were obtained in very good to excellent yields. This protocol is mild and efficient compared to other methods.     

An Efficient One-Pot Synthesis of 2-Hydroxyalkyl Dithiocarbamates

Abstract

In the presence of anhydrous potassium phosphate, epoxides reacted with carbon disulfide and primary or secondary amines in acetone to give the corresponding 2-hydroxyalkyl dithiocarbamates regioselectively in moderate to good yield.     

An Efficient One-Pot Synthesis of Triamides and Amidodiesters

An efficient one-pot procedure has been proposed for the synthesis of compounds containing three carboxamide groups or one carboxamide and two ester groups. The procedure is based on three-component condensation of alkyl isocyanides with 5-alkylidene- or 5-arylmethylene-substituted Meldrum's acids in the presence of such nucleophiles as phenols and amines.     

Convenient, Efficient One-Pot Synthesis of Ferrocenylcyanide

In asymmetric catalysis, chiral (central chiral, planar chiral, axial chiral) ferrocenylligands is one of the most successful class of auxiliaries in recent years, and some ofthem have reached the stage of industrial applications'. But many challenges remain forthe synthesis of the intermediate. One of them is how to get ferrocenylcyanide I directlyfrom ferrocenecarboxyaldehyde 2, which can be easily prepared according to thecorresponding literature2. As far as known, I is an important interm…     

An Efficient One-Pot Synthesis of N-Methoxy-N-methylamides from Carboxylic Acids

Abstract

Several N-methoxy-N-methylamides were prepared by the reaction of the corresponding carboxylic acids with N,O-dimethylhydroxylamine hydrochloride at room temperature using trichloromethyl chloroformate in the presence of triethylamine in excellent yields.     

An Efficient,Basic Resin-Mediated,One-Pot Synthesis of Dithiocarbazates Through Alcoholic Tosylates

A quick and efficient, one-pot synthesis of dithiocarbazates was accomplished in high yields by the reaction of various alcoholic tosylates of primary, secondary, and tertiary alcohols, with substituted hydrazines using an Amberlite IRA 400 (basic resin)/CS ₂ system. The reaction conditions are mild with simpler work-up procedures than previously reported methods.     

An Efficient One-Pot Synthesis of Hippuric Acid Ethyl Ester Derivatives

A rapid, one-pot procedure is described for the preparation of the ethyl esters of a number of ring-substituted N-benzoyl glycine (hippuric acid) derivatives from readily-available starting materials.     

Efficient One-Pot Synthesis of Jm3100

A facile synthesis of JM3100 was reported. This strategy could also be successfully applied in the cyclen series.     

Efficient and Convenient One-Pot Synthesis of Dioxadiazaphophepines

The reaction of vicinal dioxime with sodium hydride in dry THF followed by addition of dichlorophosphates or dichlorothiophosphates yields 2-oxo-1,3,4,7-dioxadiazaphosphepines and 2-thioxo-1,3,4,7-dioxodiazaphosphepines in moderate to good overall yields. The products are characterized by elemental analyses, molecular weights and spectral (IR, ¹H, ¹³C and ³¹P NMR) studies. A salt elimination route is used for the synthesis of titled heterocycles.     

Efficient Three-Component One-Pot Synthesis of 4H-Pyrans

Russian Journal of Organic Chemistry - Clean, practical, and efficient electrochemical synthesis of pharmaceutically relevant 4H-pyran derivatives by one-pot three-component combination of an aryl...     

Triton-B-Catalyzed,Efficient, One-Pot Synthesis of Carbazates Through Alcoholic Tosylates

A quick, efficient, one-pot synthesis of carbazates was accomplished in high yields by the reaction of various tosylates of primary, secondary, and tert alcohols, with a variety of substituted hydrazines using the benzyltrimethylammonium hydroxide (Triton-B)/CO₂ system. The reaction conditions are mild with simpler workup procedures than the reported methods.     

Synthesis of Pyrimidines,Thienopyrimidines, and Pyrazolopyrimidines

5-Ethoxycarbonyl-4-methyl-2-phenylpyrimidin-6(1H)-thione ( 3 ), which was prepared from the reaction of ethyl g -aminocrotonate 1 with benzoyl isothiocyanate ( 2 ) in refluxing acetone, was reacted with a series of halopgenated reagents to give S-alkyl derivatives 4a-g . Upon treatment of compounds 4a-c with sodium ethoxide were cyclized into thienopyrimidine 10a-c . Pyrimidinethione 3 was reacted with hydrazine hydrate to give hydroxypyrazolopyrimidine derivative 6 . The later compound was obtained by heating compound 4a with hydrazine hydrate under neat conditions, but when the reaction was carried using hydrazine hydrate in ethanol, the corresponding carbohydrazide 5 was produced.     

Triton-B-Catalyzed,Efficient, One-Pot Synthesis of Dithiocarbazates Through Alcoholic Tosylates

A quick, efficient, one-pot synthesis of dithiocarbazates was accomplished in high yields by the reaction of various tosylates of primary, secondary, and tertiary alcohols with a variety of substituted hydrazines using the benzyl–trimethylammonium hydroxide (Triton-B)/CS₂ system. The reaction conditions are mild with simpler workup procedures than the reported methods.     

透明质酸三糖模拟物的高效合成

设计合成了2个透明质酸(HA)模拟物1和2, 通过最小基团MeO的引入修饰, 模拟天然HA片段的特性, 用于透明质酸合成酶(HAS)催化机理与抑制剂的研究.     

An Efficient One-Pot Synthesis of 3-(2-Benzothiazolyl)coumarins

Some 3-(2-benzothiazolyl)coumarin imines and 3-(2-benzothiazolyl)coumarins are prepared from 2-benzothiazolylacetonitrile and 2-hydroxybenzaldehydes in ethanol in the presence of catalytic amount of NaOH.     

The Efficient Synthesis of Two Prostaglandin Intermediates

This paper presents new synthetic routes for methyl cis-7-iodo-5-heptenoate (7) and 3-hydroxycyclopent-2-enone (15a), useful intermediates in the synthesis of prostanoids.     

Triton-B Catalyzed Efficient One-Pot Synthesis of Dithiocarbamate Esters

Summary. A novel process for the one-step chemoselective conversion of alkyl halides into dithiocarbamates as protected amines was developed using benzyltrimethylammonium hydroxide (Triton-B) in presence of carbon disulfide. Thus, dithiocarbamates of different amines were prepared in very good to excellent yields. This protocol is mild, chemoselective, and efficient compared to other methods. Present address: Institute of Organic and Biomolecular Chemistry, Georg–August University, D-37077 G?ttingen, Germany