Recent heterocyclic compounds from marine invertebrates: Structure and synthesis

A large variety of unique heterocyclic natural marine products, without terrestrial counterparts, have been isolated from marine invertebrates, mainly sponges, ascidians, and soft corals. Many of these compounds display interesting biological activity. In this review, we report our recent studies on nitrogen-containing heterocyclic compounds ("alkaloids"), as well as some containing sulfur and oxygen, which have been isolated from Red Sea and Indo-Pacific organisms, and discuss progress on the synthesis of these natural products and structural analogs.

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Chemical Diversity and Biological Activity of Secondary Metabolites Isolated from Indonesian Marine Invertebrates

Molecules ◽

10.3390/molecules26071898 ◽

2021 ◽

Vol 26 (7) ◽

pp. 1898

Author(s):

Fauzia Izzati ◽

Mega Ferdina Warsito ◽

Asep Bayu ◽

Anggia Prasetyoputri ◽

Akhirta Atikana ◽

...

Keyword(s):

Natural Products ◽

Bioactive Compounds ◽

Marine Natural Products ◽

Biological Function ◽

Marine Invertebrates ◽

Biological Activities ◽

Structural Diversity ◽

Chemical Diversity ◽

Soft Corals ◽

High Chemical

Marine invertebrates have been reported to be an excellent resource of many novel bioactive compounds. Studies reported that Indonesia has remarkable yet underexplored marine natural products, with a high chemical diversity and a broad spectrum of biological activities. This review discusses recent updates on the exploration of marine natural products from Indonesian marine invertebrates (i.e., sponges, tunicates, and soft corals) throughout 2007–2020. This paper summarizes the structural diversity and biological function of the bioactive compounds isolated from Indonesian marine invertebrates as antimicrobial, antifungal, anticancer, and antiviral, while also presenting the opportunity for further investigation of novel compounds derived from Indonesian marine invertebrates.

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Chemical warfare in the sea: The search for antibiotics from Red Sea corals and sponges

Pure and Applied Chemistry ◽

10.1351/pac-con-08-10-07 ◽

2009 ◽

Vol 81 (6) ◽

pp. 1113-1121 ◽

Cited By ~ 28

Author(s):

Dovi Kelman ◽

Yoel Kashman ◽

Russell T. Hill ◽

Eugene Rosenberg ◽

Yossi Loya

Keyword(s):

Natural Products ◽

Chemical Defense ◽

Red Sea ◽

Close Association ◽

Marine Sponges ◽

Resistant Bacteria ◽

Rrna Gene ◽

Soft Corals ◽

Strong Activity ◽

Screening Programs

Marine sponges and corals are widely recognized as rich sources of novel bioactive natural products. These organisms are frequently colonized by bacteria. Some of these bacteria can be pathogenic or serve as beneficial symbionts. Therefore, these organisms need to regulate the bacteria they encounter and resist microbial pathogens. One method is by chemical defense. Antimicrobial assays performed with extracts of 23 Red Sea corals and sponges against bacteria isolated from their natural environment revealed considerable variability in antimicrobial activity. Soft corals exhibited appreciable activity; sponges showed variability, and stony corals had little or no activity. Among the soft corals, Xenia macrospiculata exhibited the highest activity. Bioassay-directed fractionation of the extract indicated that the activity was due to a range of compounds, one of which was isolated and identified as the diterpene desoxyhavannahine. Among the sponges, Amphimedon chloros exhibited strong activity. Bioassay-directed fractionation resulted in the isolation of the pyridinium alkaloid antibiotics, the halitoxins and amphitoxins. These compounds showed selective activity against specific bacteria, rather than being broad-spectrum. They were highly active against seawater bacteria, whereas bacteria associated with the sponge were resistant. This selective toxicity may be important in enabling certain bacteria to live in close association with their sponge host while it maintains a chemical defense against microbial pathogenesis. The halitoxin-resistant bacteria were identified by 16S rRNA gene analysis as Alphaproteobacteria, closely related to other Alphaproteobacteria isolated from various marine sponges. The study of microbial communities associated with sponges and corals has important implications for the production of symbiont-derived bioactive compounds and for the use of corals and sponges as source material for microbial diversity in screening programs for natural products.

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Synthesis and Biological Potentials of Quinoline Analogues: A Review of Literature

Mini-Reviews in Organic Chemistry ◽

10.2174/1570193x16666190213105146 ◽

2019 ◽

Vol 16 (7) ◽

pp. 653-688 ◽

Cited By ~ 6

Author(s):

Leena Kumari ◽

Salahuddin ◽

Avijit Mazumder ◽

Daman Pandey ◽

Mohammad Shahar Yar ◽

...

Keyword(s):

Biological Activity ◽

Heterocyclic Compounds ◽

Building Blocks ◽

Vital Role ◽

Review Of Literature ◽

Drug Discovery Process ◽

Active Compounds ◽

Lead Compounds ◽

Synthetic Approaches ◽

Derivatives Of

Heterocyclic compounds are well known for their different biological activity. The heterocyclic analogs are the building blocks for synthesis of the pharmaceutical active compounds in the organic chemistry. These derivatives show various type of biological activity like anticancer, antiinflammatory, anti-microbial, anti-convulsant, anti-malarial, anti-hypertensive, etc. From the last decade research showed that the quinoline analogs plays a vital role in the development of newer medicinal active compounds for treating various type of disease. Quinoline reported for their antiviral, anticancer, anti-microbial and anti-inflammatory activity. This review will summarize the various synthetic approaches for synthesis of quinoline derivatives and to check their biological activity. Derivatives of quinoline moiety plays very important role in the development of various types of newer drugs and it can be used as lead compounds for future investigation in the field of drug discovery process.

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Synthesis of some New 3-Substituted Heterocyclic Compounds Containing Bridgehead Nitrogen from 2-Amino Pyridine with Study Their Biological Activity

Journal of Al-Nahrain University-Science ◽

10.22401/anjs.00.1.04 ◽

2018 ◽

Vol 00 (1) ◽

pp. 26-36

Author(s):

Naeemah Al-Lami ◽

◽

Ahmad Shaker Mahmoud ◽

Keyword(s):

Biological Activity ◽

Heterocyclic Compounds ◽

Bridgehead Nitrogen

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Discovery of cytotoxic natural products from Red Sea sponges: Structure and synthesis

European Journal of Medicinal Chemistry ◽

10.1016/j.ejmech.2021.113491 ◽

2021 ◽

Vol 220 ◽

pp. 113491

Author(s):

Safia Khan ◽

Ammar A. Al-Fadhli ◽

Supriya Tilvi

Keyword(s):

Natural Products ◽

Red Sea

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Natural Products in Polyclad Flatworms

Marine Drugs ◽

10.3390/md19020047 ◽

2021 ◽

Vol 19 (2) ◽

pp. 47

Author(s):

Justin M. McNab ◽

Jorge Rodríguez ◽

Peter Karuso ◽

Jane E. Williamson

Keyword(s):

Natural Products ◽

Secondary Metabolites ◽

Marine Invertebrates ◽

Symbiotic Bacteria ◽

Chemical Defences ◽

Number Of Species ◽

Bioactive Secondary Metabolites ◽

Potential Sources ◽

Polyclad Flatworms

Marine invertebrates are promising sources of novel bioactive secondary metabolites, and organisms like sponges, ascidians and nudibranchs are characterised by possessing potent defensive chemicals. Animals that possess chemical defences often advertise this fact with aposematic colouration that potential predators learn to avoid. One seemingly defenceless group that can present bright colouration patterns are flatworms of the order Polycladida. Although members of this group have typically been overlooked due to their solitary and benthic nature, recent studies have isolated the neurotoxin tetrodotoxin from these mesopredators. This review considers the potential of polyclads as potential sources of natural products and reviews what is known of the activity of the molecules found in these animals. Considering the ecology and diversity of polyclads, only a small number of species from both suborders of Polycladida, Acotylea and Cotylea have been investigated for natural products. As such, confirming assumptions as to which species are in any sense toxic or if the compounds they use are biosynthesised, accumulated from food or the product of symbiotic bacteria is difficult. However, further research into the group is suggested as these animals often display aposematic colouration and are known to prey on invertebrates rich in bioactive secondary metabolites.

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