scholarly journals Naturally Occurring Homoisoflavonoids: Phytochemistry, Biological Activities and Synthesis

2007 ◽  
Vol 2 (4) ◽  
pp. 1934578X0700200 ◽  
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.

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

Biomolecules ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 832
Author(s):  
Hana Vylíčilová ◽  
Magdaléna Bryksová ◽  
Vlasta Matušková ◽  
Karel Doležal ◽  
Lucie Plíhalová ◽  
...  
Keyword(s):  
Plant Species ◽  
Biological Activities ◽  
Plant Biotechnology ◽  
Biological Properties ◽  
In Planta ◽  
Active Growth ◽  
Naturally Occurring ◽  
Low Concentrations ◽  
Growth Promoting

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.

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

2019 ◽  
Vol 14 (5) ◽  
pp. 1934578X1984581 ◽  
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.

Development and characterization of electrospun curcumin-loaded antimicrobial nanofibrous membranes

2020 ◽  
pp. 004051752092551
Author(s):  
Javeed A Awan ◽  
Saif Ur Rehman ◽  
Muhammad Kashif Bangash ◽  
Fiaz Hussain ◽  
Jean-Noël Jaubert
Keyword(s):  
Biological Activities ◽  
Research Work ◽  
Medical Applications ◽  
Electrospinning Technique ◽  
Naturally Occurring ◽  
Wide Range ◽  
Nanofibrous Membranes ◽  
Antimicrobial Barrier ◽  
Anti Hiv

Curcumin is a naturally occurring hydrophobic polyphenol compound. It exhibits a wide range of biological activities such as antibacterial, anti-inflammatory, anti-carcinogenic, antifungal, anti-HIV, and antimicrobial activity. In this research work, antimicrobial curcumin nanofibrous membranes are produce by an electrospinning technique using the Eudragit RS 100 (C19H34ClNO6) polymer solution enriched with curcumin. The morphology and chemistry of the membrane are analyzed using scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) spectroscopy. Kirby Bauer disk diffusion tests are carried out to examine the antibacterial effectiveness of the membrane. Experimental results show that the nanofibers produced are of uniform thickness morphology and curcumin is successfully incorporated into the nanofibrous mat, while no chemical bonding was observed between curcumin and the polymer. The antimicrobial curcumin nanofibrous membranes can be effectively applied as antimicrobial barrier in a wide variety of medical applications such as wound healing, scaffolds, and tissue engineering.

Chemical principles of Boophone, Nerine, Crossyne, Clivia, Cryptostephanus, Haemanthus and Scadoxus of the South African Amaryllidaceae and their biological properties

Planta Medica ◽  
2021 ◽  
Author(s):  
Jerald Nair ◽  
Johannes Van Staden
Keyword(s):  
South African ◽  
Biological Activities ◽  
Structural Diversity ◽  
Biological Properties ◽  
Isoquinoline Alkaloid ◽  
Flowering Plant ◽  
New Information ◽  
Regulatory Effects ◽  
Plant Families ◽  
Antioxidant Effects

The Amaryllidaceae features prominently amongst bulbous flowering plant families. Accommodating about a third of its species, South Africa affords a sound basis for Amaryllidaceae plant research. Boophone, Nerine, Crossyne, Clivia, Cryptostephanus, Haemanthus and Scadoxus have been well-represented in such endeavors. The account herein summarizes the studies undertaken between 2013-2020 on these genera in regards to their chemical and biological characteristics. A total of 136 compounds comprising 63 alkaloids and 73 non-alkaloid entities were described during this period from eighteen members of the title genera. The alkaloids were reflective of the structural diversity found in eight isoquinoline alkaloid groups of the Amaryllidaceae. Of these, the crinane (29 compounds), lycorane and homolycorine (11 compounds each) groups were the most-represented. The non-alkaloid substances were embracive of the same number of unrelated groups including, acids, phenolics, flavonoids and triterpenoids. A wide variety of assays were engaged to ascertain the biological activities of the isolated compounds, notably in regards to cancer and motorneuron-related diseases. There were also attempts made to determine the antimicrobial, anti-inflammatory and antioxidant effects of some of the substances. New information has also emerged on the herbicidal, insecticidal and plant growth regulatory effects of selected alkaloid principles. Coupled to the biological screening measures were in instances probes made to establish the molecular basis to some of the activities, particularly in relation to cancer and Parkinsonʹs disease.

Combinatorial Synthesis of Novel 3/5(3,5)-(Di)nitro/chloropaeonol Carbonyl Hydrazone Derivatives as Nematicidal Agents

2021 ◽  
Vol 24 ◽  
Author(s):  
Genqiang Chen ◽  
Lina Zhu ◽  
Yanfei Xia ◽  
Jinming Yang ◽  
Song Zhang ◽  
...  
Keyword(s):  
High Efficiency ◽  
Biological Activities ◽  
Science Research ◽  
Nematicidal Activity ◽  
Effective Control ◽  
Root Bark ◽  
Naturally Occurring ◽  
Whole Plant ◽  
Wide Range

Background: Developing the high-efficiency and low-risk small-molecule green-nematocide is the key of effective control of the nematodes. Paeonol, is a naturally occurring phenolic compound, isolated from the root bark of Paeonia suffruticosa and the whole plant of Cynanchum paniculatum. Due to its crucial phenolic ketone skeleton, modern biological science research has indicated that paeonol has a wide range of biological activities. The structural modification of paeonol into paeonol carbonyl hydrazone derivatives is a potential approach for the development of novel nematodes, which showed more toxicity than paeonol. However, there are no reports on the nematicidal activity of paeonol carbonyl hydrazone derivatives to control Heterodera glycines. Results: We always endeavor to discover and develop biorational natural products-based pesticidal agents, 4 significant intermediates and 21 novel 3/5(3,5)-(di)nitro/chloropaeonol carbonyl hydrazone derivatives were prepared, and their structures well characterized by 1H NMR, HRMS, MS, and mp. Due to the steric hindrance, the substituents on the C=N double bond of all hydrazine compounds adopted E configuration. Results of nematicidal activity revealed that, among all compounds, especially 5-nitropaeonol (5) and 3,5-dinitropaeonol (7) displayed the most potent nematicidal activity H. glycines in vivo with LC50 values of 0.0323 and 0.0367 mg/mL, respectively. Conclusion: It suggested that for the 3/5(3,5)-(di)nitro/chloropaeonol carbonyl hydrazone derivatives, a nitro group introduced at C5 position of 1 was necessary for obtaining the potent compound as nematicidal agents. These preliminary results will pave the way for further modification of paeonol in the development of potential new nematicides.

scholarly journals Oxazolidinones as Chiral Auxiliaries in the Asymmetric 1,4-Conjugate Addition Reaction Applied to the Total Synthesis of Natural Products: A Supplemental Mini-Review

2018 ◽  
Vol 15 (1) ◽  
pp. 3-20 ◽  
Author(s):  
Vahideh Zadsirjan ◽  
Majid M. Heravi
Keyword(s):  
Total Synthesis ◽  
Biological Activities ◽  
Conjugate Addition ◽  
Chiral Auxiliary ◽  
Addition Reactions ◽  
Chiral Auxiliaries ◽  
Complex Molecules ◽  
Total Syntheses ◽  
Naturally Occurring ◽  
Wide Range

Background: The most frequently used chiral auxiliaries, oxazolidinones (Evans' oxazolidinones) have been employed in 1,4-congugate addition reactions to α,β-unsaturated carbonyl compounds. Supplementary to our previous reports in this mini-review, we attempted to underscore the applications of this strategy in a step (steps) in the total synthesis of some naturally occurring compounds exhibiting diverse biological activities. Objective: In this mini-review, we try to underscore the applications of oxazolidinones (Evans’ oxazolidinones) in 1,4-congugate addition reactions to α,β-unsaturated carbonyl in the total synthesis of some naturally occurring compounds exhibiting diverse biological activities. Conclusion: In spite of well-known superiority of asymmetric catalyzed reactions, the use of auxiliarycontrolled reactions are still considered as commanding, vital and sometimes as only tools in the generation of stereogenic centers during the construction of complex molecules and total synthesis of naturally occurring compounds. The commercial availability, or readily accessibility of a wide variety of chiral amino alcohols as starting materials to synthesize a wide range of oxazolidinones is the merits of them. In addition, the ease of removal and subjection to various and diverse stereoselective reactions make oxazolidinones as the ideal and superior chiral auxiliaries. In this regard, they were successfully used in asymmetric 1,4-conjugate addition reactions with high stereoselectivities. The high degree of asymmetric induction can be attributed to the rigid chelation of N-acyloxazolidinones with metal ions, as well as the covering of one face of the system by the bulkiness of 4-substituent. In summary, in this report, the importance of the applications of chiral oxazolidinones as suitable chiral auxiliaries in the stereoselective, 1,4-conjugate addition reactions in asymmetric synthesis and in particular, the total synthesis of naturally occurring compounds and some complex molecules were underscored. Noticeably, in these total syntheses, this chiral auxiliary is controlling the stereochemistry of a newly created stereogenic center as well as preserving the configuration of other chiral centers, which already have been presented in the precursor. General methods have been established for the attachment of the chiral auxiliary as a moiety to the substrate molecule in high to excellent yields. At the end of these reactions, this auxiliary can be easily removed leaving various desired reactive motifs for the next step in multi-step synthesis.

scholarly journals ANTIOXIDANT POTENTIAL OF PIPERIDINE CONTAINING COMPOUNDS-A SHORT REVIEW

2018 ◽  
Vol 11 (8) ◽  
pp. 66
Author(s):  
Manjusha R K ◽  
Shaheen Begum ◽  
Arifa Begum ◽  
Bharathi K
Keyword(s):  
Biological Activities ◽  
Short Review ◽  
Heterocyclic Ring ◽  
Antioxidant Potential ◽  
Naturally Occurring ◽  
Antioxidant Profile ◽  
Antioxidant Agents ◽  
Wide Range ◽  
Privileged Scaffold ◽  
Candidate Molecule

Piperidine is a saturated heterocyclic ring, considered as a privileged scaffold in view of its role in wide range of biological activities. Piperidine is good candidate molecule for obtaining potent antioxidant agents. The planar nature of this heterocyclic nucleus allows the introduction of substituent groups at different positions on the ring. In the present review, the antioxidant profile of piperidine containing compounds has been focused. The compounds were classified into naturally occurring piperidines, unsaturated piperidines, N-substituted piperidines, piperamides, piperanols, piperidine oximes, and hydrazides.

scholarly journals Microbiological and Antioxidant Activity of Phenolic Compounds in Olive Leaf Extract

Molecules ◽  
2020 ◽  
Vol 25 (24) ◽  
pp. 5946
Author(s):  
Dragana Borjan ◽  
Maja Leitgeb ◽  
Željko Knez ◽  
Maša Knez Hrnčič
Keyword(s):  
Phenolic Compounds ◽  
Leaf Extract ◽  
Biological Activities ◽  
Olive Leaf ◽  
Olive Leaves ◽  
Olive Leaf Extract ◽  
Antimicrobial Potential ◽  
Isolation And Characterization ◽  
Wide Range

According to many reports, phenolic compounds isolated from olive leaves have very good biological activities, especially antimicrobial. Presently, the resistance of microorganisms to antibiotics is greater than ever. Therefore, there are numerous recent papers about alternative solutions for inhibiting their influence on human health. Olive leaf is studied as an important source of antimicrobials with low cost and used in medicine. Numerous publications on involving green technologies for isolation of active compounds from olive leaves have appeared over the past few decades. The present review reports on current knowledge of the most isolated phenolic compounds from olive leaf extract as well as methods for their isolation and characterization. This paper uses recent research findings with a wide range of study models to describe the antimicrobial potential of phenolic compounds. It also describes the vast range of information about methods for determination of antimicrobial potential focusing on effects on different microbes. Additionally, it serves to highlight the role of olive leaf extract as an antioxidants and presents methods for determination of antioxidant potential. Furthermore, it provides an overview of presence of enzymes. The significance of olive leaves as industrial and agricultural waste is emphasized by means of explaining their availability, therapeutic and nutritional effects, and research conducted on this field.

scholarly journals The progesterone-like action of testosterone and certain related compounds

1937 ◽  
Vol 121 (825) ◽  
pp. 574-579 ◽  
Keyword(s):  
Corpus Luteum ◽  
Small Dose ◽  
Specific Activity ◽  
Biological Properties ◽  
Similar Activity ◽  
Naturally Occurring ◽  
Chemical Constitution ◽  
General Investigation ◽  
Male Hormones ◽  
Related Compounds

The isolation of naturally occurring forms of oestrogenic and male hormones was soon followed by the demonstration that similar activity might be possessed, to a greater or lesser degree, by related compounds made artificially. When progesterone was isolated from the corpus luteum it was assumed that there would be an analogous lack of specificity, and investigation was immediately begun on the effect of slight changes in chemical constitution on the power to evoke progestational prolifera­tion. In the course of this work, Butenandt and his co-workers ( see the review by Westphal, 1935) examined a large number of compounds closely related to progesterone (pregnene-3: 20-dione), but failed to find pro-gesterone-like activity in any. Among the more interesting of these inactive compounds were “dihydroprogesterone” (pregnen-20-ol-3-one), inactive in a 2•7 mg. dose; pregnenolone (3-ol-20-one), inactive in 25 mg.; pregnanedione, inactive in 50 mg.; pregnanediol, inactive in 50 mg.; pregnan-20-ol-3-one, inactive in 9 mg.; and androstenedione, inactive in 30 mg. With the possible exception of dihydroprogesterone, which was tested in only a small dose, this work seemed to establish the in­ activity of these very closely related compounds, and by implication indicated the absolute specificity of progesterone. A general investigation of the biological properties of compounds of the androsterone-testosterone series carried out in this laboratory during 1935-36 led to the examination of certain of the compounds, especially those methylated or ethylated in position 17, for progesterone-like activity ( see Ruzicka, 1936, for discussion of the chemical relationships). To our surprise, in view of Butenandt’s results, certain of these compounds proved to be active (Klein and Parkes, 1936), and fuller investigation has shown that seven of them exert the specific activity previously thought to be restricted to progesterone.

scholarly journals Linear Triquinane Sesquiterpenoids: Their Isolation, Structures, Biological Activities, and Chemical Synthesis

Molecules ◽  
2018 ◽  
Vol 23 (9) ◽  
pp. 2095 ◽  
Author(s):  
Yi Qiu ◽  
Wen-Jian Lan ◽  
Hou-Jin Li ◽  
Liu-Ping Chen
Keyword(s):  
Chemical Synthesis ◽  
Total Synthesis ◽  
Chemical Structure ◽  
Biological Activities ◽  
Structural Diversity ◽  
Structure Identification ◽  
Important Class ◽  
Soft Corals ◽  
Wide Range ◽  
New Challenges

Linear triquinane sesquiterpenoids represent an important class of natural products. Most of these compounds were isolated from fungi, sponges, and soft corals, and many of them displayed a wide range of biological activities. On account of their structural diversity and complexity, linear triquinane sesquiterpenoids present new challenges for chemical structure identification and total synthesis. 118 linear triquinane sesquiterpenoids were classified into 8 types, named types I–VIII, based on the carbon skeleton and the position of carbon substituents. Their isolation, structure elucidations, biological activities, and chemical synthesis were reviewed. This paper cited 102 articles from 1947 to 2018.

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