Current Status of Indole-Derived Marine Natural Products: Synthetic Approaches and Therapeutic Applications

Abstract

Indole is a versatile pharmacophore widely distributed in bioactive natural products. This privileged scaffold has been found in a variety of molecules isolated from marine organisms such as algae and sponges. Among these, indole alkaloids represent one of the biggest, most promising family of compounds, having shown a wide range of pharmacological properties including anti-inflammatory, antiviral, and anticancer activities. The aim of this review is to show the current scenario of marine indole alkaloid derivatives, covering not only the most common chemical structures but also their promising therapeutic applications as well as the new general synthetic routes developed during the last years.

Two 5-Methoxyindole Carboxylic Acid-Derived Hydrazones of Neuropharmacological Interest: Synthesis, Crystal Structure, and Chemiluminescent Study of Radical Scavenging Properties

“…Indole core is a natural bioactive fragment present in the amino acid tryptophan, the hormones melatonin and serotonin, the tryptophan-derived compounds indole-3-propionic acid (IPA), indole-3-propionamide (IPAM), and indole-3-carbaldehyde (I3A), produced biosynthetically in gut microbiota [1,2], and is present in various alkaloids from plants, fungi, sponges, tunicates, and bryozoans [3][4][5][6][7][8]. The indolyl fragment is part of the structure of some commercial drugs and controlled substances as well-the antiarrhythmic drug ajmaline [9], physostigmine used for anticholinergic poisoning treatment [10] and the antimitotic agent vincristine [11], the psychoactive compounds ibogaine, psilocybin, and LSD [12].…”

In(OTf)3-catalyzed formal (4 + 3) cycloaddition reactions of 3-benzylideneindoline-2-thiones with 2-indolylmethanols

“…To date, numerous natural and synthetic indole derivatives have been reported as anticancer, anti-anxiety, anti-inflammatory and antihypertensive agents. 1 synthetic chemists have made substantial efforts to develop novel building blocks and catalytic strategies to streamline the synthesis of these privileged scaffolds. 2 In the past decade, various indole-based molecules, such as vinylindoles, 3 indolylmethanols, 4 indoline-2-thiones, 5 iminoindolines, 6 and others 7 have emerged as powerful two-, three- and four-atom building blocks for the synthesis of structurally diverse indole-fused heterocycles.…”