Shan-Shan Wu

Synthesis of Isoxazolo[5,4-b]pyridines by Microwave-Assisted Multi-Component Reactions in Water

A series of new polycyclic-fused isoxazolo[5,4-b]pyridines were obtained by a one-pot tandem reaction under microwave irradiation in water. Without any use of additional reagent or catalyst, the synthetic protocol represents a green one and makes this methodology suitable for library synthesis in drug discovery efforts.

Design and microwave-assisted synthesis of naphtho[2,3-f]quinoline derivatives and their luminescent properties.

A sequential three-component reaction of an aromatic aldehyde with an equimolar amount of 2-aminoanthracene and cyclic 1,3-dicarbonyl compounds (such as tetronic acid, 5,5-dimethyl,3-cyclohexanedione, 1,3-indanedione, 3H-chromene-2,4-dione, quinoline-2,4(1H, 3H)-dione and barbituric acid) in acidic medium under microwave irradiation has been developed. In this one-pot reaction, a series of unusual fused heterocyclic compounds, naphtho[2,3-f]quinoline derivatives, were synthesized. This method has the advantages of operational simplicity, increased safety for small-scale fast synthesis, and minimal environmental impact. Most distinctively, this new class of naphtho[2,3-f]quinoline derivatives exhibit good luminescent properties in the ethanol solution, which can be used potentially as organic electroluminescent (EL) media.

A diversity-oriented synthesis of pyrazolo[4,3-f]quinoline derivatives with potential bioactivities via microwave-assisted multi-component reactions

Six new series of pyrazolo[4,3-f]quinoline derivatives with potential bioactivities were synthesized by the three-component reactions of aromatic aldehydes, 5-aminoindazole, and various cyclic 1,3-dicarbonyl compounds under microwave irradiation. This protocol has the valuable features of structural diversity of products, broader substrate scope, operational simplicity, high yields, and short reaction time. Moreover, the structure of compound 88a was confirmed by an X-ray crystallographic analysis and attested to the chemoselectivity of reaction where 1-methyl barbituric acid participated.

One-Step Efficient Synthesis of Pyrazolo[3,4-f]quinoline Derivatives Under Microwave Irradiation

A series of new pyrazolo[3,4-f]quinoline derivatives were synthesized by multicomponent reactions of equimolar amounts of aromatic aldehydes 1, barbituric acids 2 (barbituric acid or 1,3-dimethyl barbituric acid), and 5-aminoindazole 3 in mixed solvent of glacial acetic acid and ethylene glycol (2:1, v/v) without catalyst under microwave irradiation. This one-pot protocol has the advantage of good yields (91–94%), simple workup procedure, and short reaction times (5–6 min).

Microwave-assisted combinatorial synthesis of new 3-pyrimidin-5-ylpropanamides via a solvent-dependent chemoselective reaction.

A series of new 3-pyrimidin-5-ylpropanamides was selectively synthesized via a microwave-assisted, chemoselective reaction of arylidene-Meldrums acid, 6-hydroxypyrimidin-4(3H)-one, and structurally diverse amines including (S or R)-1-phenylethanamine, cyclohexanamine, and cyclopentanamine depended on nature of solvents. In this reaction, the utilization of HOAc as a solvent leads to 3-pyrimidin-5-ylpropanamides, whereas water as reaction media results in the spiro[5.5]undecane-1,5,9-triones from same starting materials. This method has the advantages of short synthetic route, operational simplicity, increased safety for small-scale high-speed synthesis, and minimal environment impact.