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Regulation of Bio-systems in a clean, simple, and efficient way is important for the design of smart bio-interfaces and bioelectronic devices. Light as a non-invasive mean to control the activity of a protein enables spatial and temporal control far superior to other chemical and physical methods. The ability to regulate the activity of a catalytic enzyme in a biofuel-cell reduces the waste of resources and energy and turns the fuel-cell into a smart and more efficient device for power generation. Here we present a microbial-fuel-cell based on a surface displayed, photo-switchable alcohol dehydrogenase. The enzyme was modified near the active site using non-canonical amino acids and a small photo-reactive molecule, which enables reversible control of enzymatic activity. Depending on the modification site, the enzyme exhibits reversible behavior upon irradiation with UV and visible light, in both biochemical, and electrochemical assays. The change observed in power output of a microbial fuel cell utilizing the modified enzyme was almost five-fold, between inactive and active states., (© 2018 Wiley Periodicals, Inc.)

Phospho-ceramide analogue-1 (PCERA-1), a synthetic analogue of ceramide-1-phosphate (C1P), has been previously shown to act as a potent modulator of macrophage activity and inflammation. We have developed an efficient synthesis of PCERA-1 from readily available starting materials, and designed and prepared derivatives of this analogue, including a photoaffinity probe to tag and identify putative proteins that bind PCERA-1.

A Cu-mediated unprecedented cascade reaction in the presence of air afforded a conceptually new synthesis of 2,2'-spirobiindole derivatives. This reaction proceeds via the rearrangement of several bonds in a cyclopenta[b]indole framework including a facial selective intramolecular ring closure. The potential of this method is highlighted in the straightforward and single step synthesis of a paullone like compound.

A Cu-catalyzed new sequence involving the Ullmann type intermolecular C-C followed by an intramolecular C-N coupling and then intramolecular aza-Michael type addition (and oxidation) in a single pot afforded various fused N-heterocyclic acetic acid derivatives as inhibitors of PDE4.

A conceptually new and general strategy has been developed for the construction of a benzimidazole or a benzoxazole ring fused with isoquinolinone affording a diverse and unique class of small molecules as potential and novel inhibitors of PDE4.

A rapid, versatile and one-pot Cu-mediated domino reaction has been developed for facile assembly of two six membered fused N-heterocyclic rings leading to novel small molecules as potential inhibitors of PDE4.

A conceptually new and straightforward introduction of sulfonyl groups at the C-7 position of an indole ring has been achieved via AlCl(3) mediated unexpected regioselective sulfonyl group migration for N-alkyl/aryl/heteroarylsulfonyl indoles affording potential inhibitors of Mycobacterium tuberculosis H37Rv chorismate mutase.

A series of novel N-aryl substituted thieno[2,3-d]pyrimidin-4(3H)-ones were designed and synthesized as potential inhibitors of chorismate mutase. Synthesis of this class of compounds was carried out by using Cu-mediated C-N bond forming reaction between thieno[2,3-d]pyrimidin-4(3H)-ones and aryl boronic acids. The reaction can be performed in an open flask as the conversion was found to be not sensitive to the presence of air or atmospheric moisture. A range of compounds were prepared by using this method and single crystal X-ray diffraction study was performed using a representative compound. In vitro pharmacological data of some of the compounds synthesized along with dose response studies using active molecules are presented. In silico interactions of these molecules with chorismate mutase are also presented., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Novel thieno[2,3-d]pyrimidines containing a cyclohexane ring fused with a six- or five-membered heterocyclic moiety along with a benzylic nitrile were designed as potential inhibitors of PDE4. Expeditious synthesis of these compounds was carried out via a multi-step sequence consisting of a few key steps such as Gewald reaction, Dieckmann type cyclisation and Krapcho decarboxylation. This newly developed strategy involved construction of the thienopyrimidine ring followed by the cyclohexanone moiety and subsequently the fused heterocyclic ring. A number of thieno[2,3-d]pyrimidine based derivatives were synthesized using this method some of which showed promising PDE4B inhibitory properties. One of them was tested for PDE4D inhibition in vitro and dose dependent inhibition of TNF-α. A few selected molecules were docked into the PE4B protein the results of which showed good overall correlations to their observed PDE4B inhibitory properties in vitro. The crystal structure analysis of representative compounds along with hydrogen bonding patterns and molecular arrangement present within the molecule is described.

Novel thieno[3,2-c]pyran-4-one based small molecules were designed as potential anticancer agents. Expeditious synthesis of these compounds was carried out via a multi-step sequence consisting of few steps such as Gewald reaction, Sandmeyer type iodination, Sonogashira type coupling followed by iodocyclization and then Pd-mediated various C-C bond forming reactions. The overall strategy involved the construction of thiophene ring followed by the fused pyranone moiety and then functionalization at C-7 position of the resultant thieno[3,2-c]pyran-4-one framework. Some of the compounds synthesized showed selective growth inhibition of cancer cells in vitro among which two compounds for example, 5d and 6c showed IC(50) values in the range of 2.0-2.5 μM. The crystal structure analysis of an active compound along with hydrogen bonding patterns and molecular arrangement present within the molecule is described., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Molecular iodine facilitated the reaction of 5,5-dimethyl-1,3-cyclohexanedione with aromatic aldehydes in iso-propanol affording a variety of 1,8-dioxo-octahydroxanthenes in high yields. Most of the compounds synthesized showed good anti-proliferative properties in vitro against three cancer cell lines and 9-(2-hydroxyphenyl)-3,3,6,6-tetramethyl-3,4,5,6,7,9-hexahydro-1H-xanthene-1,8(2H)-dione possessing a 2-hydroxy phenyl group at C-9 position was found to be promising. Further structure elaboration of the same compound and the crystal structure analysis and hydrogen bonding patterns of another compound that is, 9-(4-methoxyphenyl)-3,3,6,6-tetramethyl-3,4,5,6,7,9-hexahydro-1H-xanthene-1,8(2H)-dione prepared by using this methodology is presented., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

A rapid and direct access to N-aryl substituted fused triazinone derivatives has been accomplished via N-arylation of 1,2,3-triazin-4-one ring involving a Cu-mediated coupling between triazinone derivatives and aryl boronic acids. A combination of Cu(OAc)(2)-Et(3)N in 1,2-dichloroethane was found to be effective and various fused triazinone derivatives have been prepared by using this methodology. Molecular structure of a representative compound was confirmed by single crystal X-ray diffraction study. The scope and limitations of this reaction is discussed. Some of the compounds synthesized were tested for chorismate mutase inhibitory properties in vitro. The in vitro dose response study of an active compound is presented., (Copyright © 2011 Elsevier Ltd. All rights reserved.)