Diversified Synthetic Strategies for Pyrroloindoles: An Overview

Abstract

In current scenario, heterocyclic compounds' role in medicinal chemistry has been tremendously increased as they possess wide number of pharmacological activities. One of the common heterocycles include indole skeleton with well‐established biological significance in field of medicinal chemistry. Fusion of indole nucleus with pyrrole heterocycle constitutes pyrroloindole scaffold, which further modifies the existing properties of indole alone. Pyrroloindole is a privileged scaffold found in various types of bioactive entities including natural compounds and exhibits wide variety of pharmacological activities like muscle relaxant, antifungal, antitumor, and antibiotic. Therefore, it is considered as attractive template for drug discovery. From several years, numbers of synthetic strategies have been reported for the synthesis of pyrroloindole and its derivatives, including also natural compounds such as amauromine, yuremamine, and chimonanthines. Here, in this review, we have tried to compile various synthetic strategies of pyrroloindole and its derivatives.

TosMIC: A Powerful Synthon for Cyclization and Sulfonylation

“…Based on our interest on synthetic chemistry [58] and medicinal chemistry, [59] we reflected that p-tosylmethyl isocyanide has become part and parcel in the construction of diversified heterocyclic scaffold and also serve as sulfonylating regent. Due to excellent reactivity and selectivity, TosMIC facilitated a broad range of chemical transformations and novel methodologies including multicomponent, domino/cascade and cycloaddition reactions.…”

Asymmetric Synthesis of Halocyclized Products by Using Various Catalysts: A State‐of‐the‐Art Review

“…These compounds have an immense biological application. [84,85] The authors used chiral anionic PTCs and other brominating agents. They carried out the reaction on a gram scale with a yield of about 96 % and enantioselectivity of about 95 % ee.…”

Pyrroloindole-Based Dynamic Combinatorial Chemistry

“…The pyrrolo[2,3-f ]indole scaffold consists of a pyrrole ring condensed with the benzene ring of an indole. This is the so-called "type I pyrroloindole" found in many natural alkaloids and also widely used in medicinal chemistry research [53,54]. It is aromatic (14 π electrons) and bears cysteine appendages on the α, α' positions that confer it water solubility and ability to be involved in disulfide exchange (Figure 1).…”