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An efficient, one-pot, solvent-free synthesis of ethyl 3,5-disubstituted-1H-pyrrole-2-carboxylate is achieved by a reaction of 1,3-disubstituted propen-2-one and ethylnitroacetate, in presence of diethylamine (Et2NH) and triethyl- phosphite (P(OEt)3) under microwave (MW) irradiation via cascade Michael-reductive cyclization. The mechanistic out- come of the reaction has also been described. This protocol establishes an easy access to disubstituted-1H-pyrrole-2- carboxylates in one pot.

Pyrrole is one of the most important azaheterocycles, due to its wide range of applications in pharmaceuticals and optoelectronic materials, coupled with its utility as an intermediate in natural products. For several decades, realisation of the scope and potential of this heterocyclic system in both the pharmaceutical and materials industries, has sparked new efforts in finding more efficient synthetic methods for the preparation of pyrrole compounds. Inspired by the importance of this system, herein, we report a review on pyrrole based pharmaceuticals, natural products and optoelectronic materials. Synthetic approaches to pyrrole from active methylenes are also reviewed together with novel reports from our laboratory recently (till 2015).

Ultrasonic-assisted, catalyst-free reactions of ninhydrin with ethyl cyanoacetate and diethyl malonate led to the unprecedented formation of an indenopyran and a spiroindenofuran viz. diethyl 4-cyano-2-hydroxy-5-oxo-4,5-dihydroindeno[1,2-b]pyran-3,4-dicarboxylate 1 and diethyl 3a′,8b′-dihydroxy-1,3,4′-trioxo-1,3,3a′,4′-tetrahydrospiro[indene-2,2′-indeno[1,2-b]furan]-3′,3′(8b′H)-dicarboxylate 3, respectively. In addition to these unprecedented results, reactions of ninhydrin with dimedone, ethyl acetoacetate and ethyl nitroacetate yielded 4b,9b-dihydroxy-7,7-dimethyl-7,8-dihydro-4bH-indeno[1,2-b]benzofuran-9,10(6H,9bH)-dione 5, ethyl 3a,8b-dihydroxy-2-methyl-4-oxo-4,8b-dihydro-3aH-indeno[1,2-b]furan-3-carboxylate 6 and 2-hydroxy-2-(nitromethyl)-1H-indene-1,3(2H)-dione 7, respectively. The structures of 1, 3, 5, 6 and 7 were determined by X-ray crystallography and attempts have been made to propose the mechanism of their formation.

One-pot synthesis of 2-aroylindoles and 2-arylquinolines has been achieved by the reductive cyclization of 3-(2-nitrophenyl)-1-arylprop-2-en-1-ones with triethylphosphite [P(OEt)3] under microwave irradiation. The formation of 2-arylquinolines by this method is unprecedented.

Introduction Rett syndrome (RS), an X-linked neurodevelopmental disorder and the common cause of mental retardation in females, is caused by methyl CpG binding protein 2 ( MECP2 ) gene mutations with a frequency of more than 95% in classical Rett patients. Majority of RS cases are sporadic but few familial cases caused by either skewed X-chromosome inactivation in healthy female carriers or mosaicism in male carriers are also reported. Most of the times, the mutation carried in a family is the same as found in affected child. Methods and results Here we report a unique family carrying non-identical MECP2 mutations in exon 2 wherein the proband with classical RS was carrying a de-novo early truncating frameshift mutation while her asymptomatic mother was carrying a missense mutation, both predicted as pathogenic mutations. Conclusions These findings further validate the importance of MECP2 mutation screening in parents of all mutation positive patients and careful evaluation of the pathogenicity of the mutation found in asymptomatic carriers before providing genetic counseling to the family. The results also propose the role of other factors including other gene mutations, environmental and epigenetics factors in modifying the expression of MECP2 mutations.

Rett syndrome (RS) is an X-linked dominant neurodevelopment disorder with normal prenatal and postnatal development till 6-18 months, followed by stagnation and regression of acquired skills. RS primarily manifests in females, and there are a few reports with males having RS. Sporadic or de novo mutations of the methyl CpG binding protein 2 (MECP2) gene have been reported in 70-90% of affected girls. Conventional methods such as fluorescence in situ hybridization, real-time PCR, southern blotting, multiplex ligation-dependent probe amplification, and DNA sequencing have been previously reported for the detection of insertions or deletions in the MECP2 gene. Here, we report detection of two deletions of 44 bp (c.1157_1200del44 or p.L386fs) and 38 bp (c.1151_1188del38 or p.P384fs) in exon 4 or C-terminal segment (CTS) region of MECP2 using a simple PCR technique that is rapid, accurate, and cost effective as compared to other techniques. The deletions were detected by routine PCR amplification followed by 2% agarose gel electrophoresis. We suggest that a simple PCR can easily detect deletions in the hotspot CTS region of the MECP2 gene and can be used for routine molecular diagnostics of RS.

Three component condensation of 1,3-diaryl-2-propen-1-ones with ethyl nitroacetate and ammonium acetate provides a convenient synthesis of 4,6-diarylated pyridin-2(1H)-ones.

Using alum and solvent-free conditions makes this methodology simple, convenient, environmentally friendly as well as cost-effective.

Ethyl 3,5-diaryl-1H-pyrrole-2-carboxylates have been synthesized in good yields from ethyl 2-nitro-5-oxo-3,5-diarylpentanoates by treatment with triethylphosphite under microwave irradiation. The integrity of the mechanism proposed has been augmented by 31P NMR and EIMS experiments.

Pyrazolylisoxazolines bearing cyclic or linear lipophilic groups (VI) and (IX), resp., are synthesized and tested for their antibacterial and antifungal activities.