A bifunctional colorimetric fluorescent probe for Hg(2+) and Cu(2+) based on a carbazole-pyrimidine conjugate: chromogenic and fluorogenic recognition on TLC, silica-gel and filter paper.

A bifunctional fluorescent probe based on a carbazole-pyrimidine conjugate for Hg(2+) and Cu(2+) detection was designed and synthesized. Probe 3 exhibits red shifts in its absorption and fluorescence spectra with significant visual color changes in the presence of these ions. The detection limits of probe 3 for these metal ions were in the nanomolar range. The probe could also be useful as a solid optical sensor for Hg(2+) and Cu(2+).

Diketopyrrolopyrrole: brilliant red pigment dye-based fluorescent probes and their applications.

The development of fluorescent probes for the detection of biologically relevant species is a burgeoning topic in the field of supramolecular chemistry. A number of available dyes such as rhodamine, coumarin, fluorescein, and cyanine have been employed in the design and synthesis of new fluorescent probes. However, diketopyrrolopyrrole (DPP) and its derivatives have a distinguished role in supramolecular chemistry for the design of fluorescent dyes. DPP dyes offer distinctive advantages relative to other organic dyes, including high fluorescence quantum yields and good light and thermal stability. Significant advancements have been made in the development of new fluorescent probes based on DPP in recent years as a result of tireless research efforts by the chemistry scientific community. In this tutorial review, we highlight the recent progress in the development of DPP-based fluorescent probes for the period spanning 2009 to the present time and the applications of these probes to recognition of biologically relevant species including anions, cations, reactive oxygen species, thiols, gases and other miscellaneous applications. This review is targeted toward providing the readers with deeper understanding for the future design of DPP-based fluorogenic probes for chemical and biological applications.

Diketopyrrolopyrrole-bitellurophene containing a conjugated polymer and its high performance thin-film transistor sensor for bromine detection.

A new bitellurophene-based π-conjugated polymer (PDPPBTe) was synthesized and its semiconducting property was utilized for detecting Br2. The PDPPBTe polymer exhibited a highly sensitive response to Br2, which was indicated by a significant variation of the drain current in thin-film transistors.

Rational design, synthesis and evaluation of chromone-indole and chromone-pyrazole based conjugates: identification of a lead for anti-inflammatory drug.

Conjugates of chromone-indole and chromone-pyrazole were screened for cyclooxygenase-2 (COX-2), cyclooxygenase-1 (COX-1) and 5-lipoxygenase (5-LOX) inhibitory activities. Compounds 8 and 9 were identified as preferred inhibitors of COX-2 over the other two enzymes. Their IC50 for COX-2 was 29 nM and 20 nM, respectively and selectivity indices (SI) for COX-2 over COX-1 was 46 and 337. NMR, mass spectral studies and molecular modelling also indicated preferential interactions of compounds 8 and 9 with COX-2. Tested on albino mice against capsaicin induced algesia, compound 8 exhibited analgesic potential comparable to diclofenac. In addition to the biological profile, the desirable physico-chemical properties of these compounds make them promising leads for anti-inflammatory drugs.

A high-mobility terselenophene and diketopyrrolopyrrole containing copolymer in solution-processed thin film transistors.

A new diketopyrrolopyrrole (DPP)-based π-conjugated copolymer containing terselenophene units has been successfully synthesized. Its hole mobility reaches around 5.0 cm(2) V(-1) s(-1) in thin film transistors made from thermally annealed films. This proves that a longer terselenophene unit induced excellent charge transport properties.

A novel tellurophene-containing conjugated polymer with a dithiophenyl diketopyrrolopyrrole unit for use in organic thin film transistors.

A new tellurophene-based π-conjugated polymer, PDTDPPTe, was synthesized. PDTDPPTe exhibits a smaller optical band gap (E(g)(opt) = 1.25 eV) than thiophene-based PDTDPPT (E(g)(opt) = 1.30 eV). Thin-film transistors comprising PDTDPPTe displayed outstanding performance (µ(max) = 1.78 cm(2) V(-1) s(-1), I(on)/I(off) = 10(5-6)).

Mechanism inspired development of rationally designed dihydrofolate reductase inhibitors as anticancer agents.

On the basis of structural analysis of dihydrofolate reductase (DHFR) (cocrystallized separately with NADPH, dihydrofolate and NADPH, trimethoprim), compounds 2 and 3 were optimized for inhibition of DHFR. Appreciable tumor growth inhibitory activities of compounds 2 and 3 over 60 human tumor cell lines were recorded. Combination of syringaldehyde and indole moieties in these two compounds was rationalized by the synthesis of compounds 4-7, 10, and 11, which were found to have less tumor growth inhibitory activities than compounds 2 and 3. Further, UV-vis and NMR spectral investigations showed significant interactions of compounds 2 and 3 with DHFR and inhibition of its catalytic activity was observed in the presence of these compounds. Therefore, modification of trimethoprim, an antibacterial drug with no tumor growth inhibition, led to the development of compounds 2 and 3 having appreciable anticancer activities that seem to be due to inhibition of DHFR.

CN- scavenger: a leap towards development of a CN- antidote.

Compound 4 removes cyanide from water and human serum in the form of compound 7 (cyano-derivative of 4) and experiments show its suitability as an antidote of CN(-) poisoning.

Synthesis and evaluation of indole, pyrazole, chromone and pyrimidine based conjugates for tumor growth inhibitory activities--development of highly efficacious cytotoxic agents.

Based upon the lead compounds 10 and 11, a number of conjugates were synthesized by the combination of chromone-pyrimidine, chromone-indolinone, chromone-pyrazole, indole-pyrimidine, indole-indolinone and indole-pyrazole moieties. Evaluation of these compounds for tumor growth inhibitory activities over 60 human tumor cell lines provided highly efficacious compounds 15, 41, 43, 66, 69, and 72 with an average GI(50) over all the 60 human tumor cell lines as 3.2 µM, 3.1 µM, 1.7 µM, 2.6 µM, 50.1 µM and 2.0 µM, respectively.

Design, synthesis and anticancer activities of hybrids of indole and barbituric acids--identification of highly promising leads.

By combining the structural features of indole and barbituric acid, new hybrid molecules were designed and synthesized. Evaluations of these molecules over 60 cell line panel of human cancer cells have identified two molecules with significant anticancer activities. Dockings of two active molecules in the active sites of COX-2, thymidylate synthase and ribonucleotide reductase indicate their strong interactions with these enzymes.