New potent cytotoxic lamellarin alkaloids from Indian ascidian Didemnum obscurum

Visible-light photoredox catalyzed synthesis of pyrroloisoquinolines via organocatalytic oxidation/[3 + 2] cycloaddition/oxidative aromatization reaction cascade with Rose Bengal

“…These alkaloids display numerous biological activities such as inhibitor of human topoisomerase I by lamellarin D [5] or inhibition of HIV integrase by lamellarin α - 20-sulfate [6–7]. Moreover lamellarin I and lamellarin K also showed potential antitumor activities [8–9]. Due to their potential biological activities, the synthesis of pyrrolo[2,1- a ]isoquinolines has become a very interesting, important and attractive goal in organic synthesis [10–20].…”

Benzoic Acid‐Promoted Intermolecular [3+2] Cycloaddition with Air as the Terminal Oxidant: General Approach toward Pyrrolo[2, 1‐a]isoquinolines

“…Pyrrolo[2, 1‐ a ]isoquinolines also represent the core structure of the lamellarin alkaloid family of natural products, which contains more than numbers and has been reported to exhibit a diverse range of biological activities . For example, lamellarin I has been reported to be a multidrug resistance inhibitor, whereas lamellarin K has been shown to display antitumor activity . Furthermore, lamellarin D has been reported to be an inhibitor of human topoisomerase I, whereas lamellarin α‐20‐sulfate has been evaluated in clinical trials as an inhibitor of HIV integrase…”

Living on pyrrolic foundations – Advances in natural and artificial bioactive pyrrole derivatives

“…Hui Fan et al, in their review on lamellarins [25] have divided them into two groups, depending on whether the central pyrrole ring is fused or not fused, proceeding to describe the structure of these compounds, their bioactivity and the methods for their preparation in great detail. The biological activity of these systems is a subject in its own right, as they have been reported to exhibit cytotoxicity and antitumour activity [26], reversal of multidrug resistance (MDR) [27], HIV-1 integrase inhibition [28], antibiotic activity [29], human aldose reductase (h-ALR2) inhibition [30], cell division inhibition [31], immunomodulation [32], antioxidant activity [28], and feeding deterrence [33], making these compounds extremely promising for pharmacological applications.…”

“…Rumbrin (32), an unusual pyrrolylpolyene, is a prime example of the fruits of biosynthetic studies on fungal pyrrolylpolyenes. It boasts a number of features in terms biological effects, particularly anticancer and cytoprotective activity.…”