Naturally Occurring and Artificial N9-Cytokinin Conjugates: From Synthesis to Biological Activity and Back

Cytokinins and their sugar or non-sugar conjugates are very active growth-promoting factors in plants, although they occur at very low concentrations. These compounds have been identified in numerous plant species. This review predominantly focuses on 9-substituted adenine-based cytokinin conjugates, both artificial and endogenous, sugar and non-sugar, and their roles in plants. Acquired information about their biological activities, interconversions, and metabolism improves understanding of their mechanisms of action and functions in planta. Although a number of 9-substituted cytokinins occur endogenously, many have also been prepared in laboratories to facilitate the clarification of their physiological roles and the determination of their biological properties. Here, we chart advances in knowledge of 9-substituted cytokinin conjugates from their discovery to current understanding and reciprocal interactions between biological properties and associated structural motifs. Current organic chemistry enables preparation of derivatives with better biological properties, such as improved anti-senescence, strong cell division stimulation, shoot forming, or more persistent stress tolerance compared to endogenous or canonical cytokinins. Many artificial cytokinin conjugates stimulate higher mass production than naturally occurring cytokinins, improve rooting, or simply have high stability or bioavailability. Thus, knowledge of the biosynthesis, metabolism, and activity of 9-substituted cytokinins in various plant species extends the scope for exploiting both natural and artificially prepared cytokinins in plant biotechnology, tissue culture, and agriculture.

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Naturally Occurring Homoisoflavonoids: Phytochemistry, Biological Activities and Synthesis

Natural Product Communications ◽

10.1177/1934578x0700200418 ◽

2007 ◽

Vol 2 (4) ◽

pp. 1934578X0700200 ◽

Cited By ~ 6

Author(s):

Berhanu M. Abegaz ◽

Joan Mutanyatta-Comar ◽

Mathew Nindi

Keyword(s):

Biological Activities ◽

Optical Rotation ◽

Biological Properties ◽

Important Class ◽

Melting Points ◽

Naturally Occurring ◽

Wide Range ◽

Plant Families ◽

Related Compounds

This review covers the phytochemical, biological properties, and synthesis of naturally occurring homoisoflavonoids. Homoisoflavonoids are a very important class of secondary metabolites whose numbers have grown from 20 in 1981 to 157 at the present time. They are found to occur in seven plant families. For the purpose of this review they are classified into five groups: 3-benzylchroman-4-ones, 3-benzylflavans, Δ3,9 and Δ2,3 3-benzylchroman-4-ones, benzocyclobutenes (scillascillins) and rearranged homoisoflavonoids (brazilin and related compounds). Biosynthetically, the 3-benzylchroman-4-ones and the 3-hydroxy-derivatives have been shown to arise from a chalcone precursor (sappanchalcone) and there is strong evidence that this isolable intermediate can be converted into the diverse structures such as the benzocyclobutenes (scillascillins) and the rearranged, brazilin-type compounds. Homoisoflavonoids possess a wide range of biological activities, including, antimicrobial, antimutagenic, anti-inflammatory, antidiabetic, etc, properties. The review also surveys the chemical synthesis of natural homoisoflavonoids. Analytical methods for the determination of these important metabolites are also reviewed. The last section is devoted to a brief review of the diagnostic NMR spectroscopic features of homoisoflavonoids. A comprehensive Table has also been compiled listing all known metabolites, their sources, melting points and optical rotation values (where available) and references.

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An Overview on Pyranocoumarins: Synthesis and Biological Activities

Current Organic Chemistry ◽

10.2174/1385272823666191025151236 ◽

2020 ◽

Vol 23 (24) ◽

pp. 2679-2721 ◽

Cited By ~ 1

Author(s):

Evangelia-Eirini N. Vlachou ◽

Konstantinos E. Litinas

Keyword(s):

Organic Compounds ◽

Antifungal Agents ◽

Biological Activities ◽

Biological Properties ◽

Pyran Ring ◽

Naturally Occurring ◽

Anti Cancer ◽

Anti Inflammatory ◽

Antibacterial And Antifungal ◽

Anti Hiv

Pyrano- and dipyranocoumarins are classes of naturally occurring organic compounds with very interesting biological activities. This review focuses on the synthetic strategies for the synthesis of pyranocoumarins and dipyranocoumarins and the biological properties of those compounds. The synthesis involves the formation of the pyran ring, at first, from a coumarin or the formation of pyranone moiety from an existing pyran. Pyranocoumarins and dipyranocoumarins present anti-HIV, anti-cancer, neuroprotective, antidiabetic, antibacterial, antifungal, anti-inflammatory activities. Especially khellactones and calanolides are usually potent and selective in anti-HIV activity. Decursin and decursinol derivatives are effective as anticancer, neuroprotective, antidiabetic, antibacterial, and antifungal agents.

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Modulation of Secondary Metabolites among Mexican Medicinal Plants by Using Elicitors and Biotechnology Techniques

10.5772/intechopen.99888 ◽

2021 ◽

Author(s):

María Adelina Jiménez-Arellanes ◽

Mariana Z. Pérez-González

Keyword(s):

Medicinal Plants ◽

Secondary Metabolites ◽

Traditional Medicine ◽

Plant Species ◽

Biological Activities ◽

Plant Biotechnology ◽

Raw Material ◽

Biological Potential ◽

Biotechnological Processes ◽

Cnidoscolus Chayamansa

Medicinal plants are being utilized as raw material and the use has increased in recent decades due that these biosynthesize compounds with several pharmacological activities. Some plant species with biological potential are of interest to the industry for preparation of drugs, phytodrugs, or food supplements. This causes overexploitation and deforestation, which endangers plant species-of-interest. In recent years, alternatives have been sought to eradicate this problem. A solution that was give and is maintained is plant biotechnology, which favors the production of active Secondary Metabolites (SMt). Plant biotechnology allows us to increase the yield of a compound-of-interest, reduces its production times and costs, and allows constant and controlled production of the raw material, and while aiding in the protection of medicinal plants that are found in danger of extinction. In the scientific literature, procuring the SMt by means of biotechnological processes is described, highlighting the study of four species from Mexican traditional medicine (Lopezia racemosa, Galphimia glauca, Cnidoscolus chayamansa, Sphaeralceae angustifolia and Buddleja cordata), and the main biological activities are as follows: anti-inflammatory, hepatoprotector, neuroprotector, anxiolytic, antitumoral, antibacterial, and antioxidant, among others.

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Ellagic Acid: A Logical Lead for Drug Development?

Current Pharmaceutical Design ◽

10.2174/1381612823666171115094557 ◽

2018 ◽

Vol 24 (2) ◽

pp. 106-122 ◽

Cited By ~ 7

Author(s):

Abolfazl Shakeri ◽

Mohammad Reza Zirak ◽

Amirhossein Sahebkar

Keyword(s):

Oxidative Stress ◽

Ellagic Acid ◽

Therapeutic Agent ◽

Biological Activities ◽

Biological Properties ◽

Mechanisms Of Action ◽

Human Diseases ◽

Pharmacological Properties ◽

Naturally Occurring ◽

The Subject

Background: Naturally occurring polyphenols are the subject of increasing attention due to their potent antioxidant activity and their marked effects on the prevention of various oxidative stress-associated diseases such as cancer. Ellagic acid (EA) is an herbal polyphenol that is structurally a condensed dimer of gallic acid. Methods: This review aims to provide a comprehensive and updated overview on the biological activities of EA and potential therapeutic applications. Results: EA is found in fruits and nuts, either in the combined form with hexahydroxydiphenic acid or in the bound form (ellagitannins). EA exhibits many biological properties such as antioxidant, anti-diabetic, anticancer and apoptosis-inducing activities. These biological and pharmacological properties are relevant to the treatment of several human diseases. Conclusion: Owing to its multiple mechanisms of action, EA represents a potential therapeutic agent against human diseases particularly cancer.

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A Brief Review on New Naturally Occurring Cembranoid Diterpene Derivatives from the Soft Corals of the Genera Sarcophyton, Sinularia, and Lobophytum Since 2016

Molecules ◽

10.3390/molecules24040781 ◽

2019 ◽

Vol 24 (4) ◽

pp. 781 ◽

Cited By ~ 14

Author(s):

Inna Rodrigues ◽

Maria Miguel ◽

Wissem Mnif

Keyword(s):

Chemical Composition ◽

Biological Activities ◽

Biological Properties ◽

Gram Negative Bacteria ◽

Soft Corals ◽

Gram Negative ◽

Naturally Occurring ◽

Chemical Variability ◽

Bacteria And Fungi ◽

Almost All

This work reviews the new isolated cembranoid derivatives from species of the genera Sarcophyton, Sinularia, and Lobophytum as well as their biological properties, during 2016–2018. The compilation permitted to conclude that much more new cembranoid diterpenes were found in the soft corals of the genus Sarcophyton than in those belonging to the genera Lobophytum or Sinularia. Beyond the chemical composition, the biological properties were also reviewed, namely anti-microbial against several Gram-positive and Gram-negative bacteria and fungi, anti-inflammatory and anti-tumoral against several types of cancer cells. In spite of the biological activities detected in almost all samples, there is a remarkable diversity in the results which may be attributed to the chemical variability that needs to be deepened in order to develop new molecules with potential application in medicine.

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Naturally Occurring Homoisoflavonoids: Phytochemistry, Biological Activities, and Synthesis (Part II)

Natural Product Communications ◽

10.1177/1934578x19845813 ◽

2019 ◽

Vol 14 (5) ◽

pp. 1934578X1984581 ◽

Cited By ~ 3

Author(s):

Berhanu M Abegaz ◽

Henok H Kinfe

Keyword(s):

Total Synthesis ◽

Biological Activities ◽

Biological Properties ◽

Caesalpinia Sappan ◽

Plant Parts ◽

Naturally Occurring ◽

Biological Sources ◽

Optical Rotations ◽

Plant Families ◽

New Compounds

This review documents all the new homoisoflavonoids (HIFs) that have been reported since 2007, whose total number has grown from 159 in 2007 to 295 at the present time. This review contains their structures, biological sources, plant parts they are obtained from, and, if reported, their optical rotations and melting points. The same classification is followed as an earlier review to ease reference to both reviews. This review takes note of the recent revision of plant families that were known to contain HIFs that have now been merged into one big family, Asparagaceae. Homoisoflavonoids also occur in Fabaceae and others. Two taxa, Ophiopogoan japonicus (Asparagaceae) and Caesalpinia sappan (Fabaceae), have been the source of many HIFs. These are briefly summarized. The biological properties of HIFs are also reviewed under the topics such as antioxidant, anti-inflammatory, antimicrobial, antidiabetic, and cytotoxic. The review also surveys the total synthesis of natural HIFs. All new compounds are classified and tabulated following the same style as the previous review. Dedicated to Professor Andrew Paul Krapcho on the occasion of his 87th Birthday.

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Isolation and identification of plant growth-promoting bacteria associated with tall fescue

Proceedings of the New Zealand Grassland Association ◽

10.33584/jnzg.2009.71.2751 ◽

2009 ◽

pp. 211-216 ◽

Cited By ~ 5

Author(s):

J. Monk ◽

E. Gerard ◽

S. Young ◽

K. Widdup ◽

M. O'Callaghan

Keyword(s):

New Zealand ◽

Plant Growth ◽

Tall Fescue ◽

Festuca Arundinacea ◽

Plant Growth Promoting Bacteria ◽

Beneficial Bacteria ◽

Isolation And Identification ◽

Naturally Occurring ◽

Plant Growth Promoting ◽

Growth Promoting

Tall fescue (Festuca arundinacea) is a useful alternative to ryegrass in New Zealand pasture but it is slow to establish. Naturally occurring beneficial bacteria in the rhizosphere can improve plant growth and health through a variety of direct and indirect mechanisms. Keywords: rhizosphere, endorhiza, auxin, siderophore, P-solubilisation

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Determination of Conformational Stability and Melting Temperature of Factor VIII at Extremely Low Concentrations

10.26226/morressier.57d6b2bfd462b8028d88cc6f ◽

2016 ◽

Author(s):

Rajiv Nayar

Keyword(s):

Factor Viii ◽

Melting Temperature ◽

Conformational Stability ◽

Low Concentrations

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Diverse chemical and biological potentials of various pyridazine and pyridazinone derivatives

10.31221/osf.io/n5xvt ◽

2019 ◽

Author(s):

Chem Int

Keyword(s):

Heterocyclic Compounds ◽

Biological Activities ◽

Wide Spectrum ◽

Biological Properties ◽

Industrial Chemical ◽

Anti Inflammatory ◽

Pyridazinone Derivatives

A series of heterocyclic compounds incorporating pyridazine moiety were for diverse biological activities. Pyridazines and pyridazinones derivatives showed wide spectrum of biological activities such as vasodialator, cardiotonic, anticonvulsant, antihypertensive, antimicrobial, anti-inflammatory, analgesic, anti-feedant, herbicidal, and various other biological, agrochemical and industrial chemical activities. The results illustrated that the synthesized pyridazine/pyridazine compounds have diverse and significant biological activities. Mechanistic insights into the biological properties of pyridazinone derivatives and various synthetic techniques used for their synthesis are also described.

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