Synthesis of isoindoles and related iso-condensed heteroaromatic pyrroles

Coumarin heterocyclic derivatives: chemical synthesis and biological activity

This review highlights the broad range of science that has arisen from the synthesis of coumarin-linked and fused heterocycle derivatives. Specific topics include their synthesis and biological activity.

Deep eutectic solvent based on choline chloride and malonic acid as an efficient and reusable catalytic system for one-pot synthesis of functionalized pyrroles

Deep eutectic solvent (DES) based on choline chloride and malonic acid was applied as catalyst and reaction medium for synthesis of pyrroles by one-pot, four-component reaction of amines, aldehydes, 1,3-dicarbonyl compounds and nitromethane.

Synthesis and photophysics of selective functionalized π-conjugated, blue light emitting, highly fluorescent C7-imidazo indolizine derivatives

Synthesis and photophysics of selective functionalized π-conjugated, blue light emitting highly fluorescent C7-imidazo indolizine derivatives.

Picomolar inhibitors of HIV reverse transcriptase featuring bicyclic replacement of a cyanovinylphenyl group

Members of the catechol diether class are highly potent non-nucleoside inhibitors of HIV-1 reverse transcriptase (NNRTIs). The most active compounds yield EC50 values below 0.5 nM in assays using human T-cells infected by wild-type HIV-1. However, these compounds such as rilpivirine, the most recently FDA-approved NNRTI, bear a cyanovinylphenyl (CVP) group. This is an uncommon substructure in drugs that gives reactivity concerns. In the present work, computer simulations were used to design bicyclic replacements for the CVP group. The predicted viability of a 2-cyanoindolizinyl alternative was confirmed experimentally and provided compounds with 0.4 nM activity against the wild-type virus. The compounds also performed well with EC50 values of 10 nM against the challenging HIV-1 variant that contains the Lys103Asn/Tyr181Cys double mutation in the RT enzyme. Indolyl and benzofuranyl analogues were also investigated; the most potent compounds in these cases have EC50 values toward wild-type HIV-1 near 10 nM and high-nanomolar activities toward the double-variant. The structural expectations from the modeling were much enhanced by obtaining an X-ray crystal structure at 2.88 Å resolution for the complex of the parent 2-cyanoindolizine 10b and HIV-1 RT. The aqueous solubilities of the most potent indolizine analogues were also measured to be ~40 μg/mL, which is similar to that for the approved drug efavirenz and ~1000-fold greater than for rilpivirine.

The chemistry of isoindole natural products

This review highlights the chemical and biological aspects of natural products containing an oxidized or reduced isoindole skeleton. This motif is found in its intact or modified form in indolocarbazoles, macrocyclic polyketides (cytochalasan alkaloids), the aporhoeadane alkaloids, meroterpenoids from Stachybotrys species and anthraquinone-type alkaloids. Concerning their biological activity, molecular structure and synthesis, we have limited this review to the most inspiring examples. Within different congeners, we have selected a few members and discussed the synthetic routes in more detail. The putative biosynthetic pathways of the presented isoindole alkaloids are described as well.

Cycloaddition-based formal C-H alkynylation of isoindoles leading to the synthesis of air-stable fluorescent 1,3-dialkynylisoindoles

Reaction of N-alkylisoindoles with (bromoethynyl)triisopropylsilane afforded 1,3-bis(triisopropylsilylethynyl) isoindoles in high yields. The formal C-H alkynylation proceeds under transition-metal-free conditions through [4 + 2] cycloaddition of the pyrrole ring of isoindole with bromoalkyne followed by ring-opening of the product.