scholarly journals SYNTHESIS, CHARACTERIZATION, ANTIFUNGAL ACTIVITY AND STRUCTURE– ACTIVITY RELATIONSHIPS: STUDY OF SOME MONO- AND DI-SCHIFF BASES

2020 ◽  
Vol 17 (34) ◽  
pp. 528-540
Author(s):  
Ekhlas Q JASIM ◽  
Hawraa K DHAIF ◽  
Munther A MUHAMMAD-ALI
Keyword(s):  
Antifungal Activity ◽  
Schiff Bases ◽  
Density Functional ◽  
Chemical Reactivity ◽  
Biological Activities ◽  
Analytical Techniques ◽  
Carbonyl Oxygen ◽  
Proton Nuclear Magnetic Resonance ◽  
Mulliken Charge ◽  
Wide Range

Schiff bases (SB) are an important type of organic compounds and have a wide range of biological activities due to commercial and pharmaceutical trading uses. The different activities of these compounds induced the researchers to synthesized and studied new types of these compounds. Two series of Schiff base derivatives were synthesized by the condensation reactions of substituted aldehydes salicylaldehyde, 4-(N,Ndimethylamino) benzaldehyde or 2,4-dimethoxybenzaldehyde with 2-amino-5-iodobenzoic acid (1:1) or with 3,5- diamenobenzoic acid (1:2) in ethanol absolute as a solvent. Different analytical techniques characterized the structure of the synthesized Schiff bases; for instance, Fourier transform infrared FT-IR and proton nuclear magnetic resonance 1H-NMR. The purity of the synthesized compounds was tested by elemental microanalysis CHN and thin layer chromatography TLC. The structural properties of the studied molecules were investigated theoretically by performing density functional theory (DFT) using the HyperChem software. The lipophilicity of the tested compounds showed that the compounds 2c, 2b, 2a, and 1c have logP values less than (5), 2.90, 3.78, 3.82 and 4.57, respectively, whereas, 1b and 1a have logP values higher than (5), 5.01 and 5.03, respectively. The Mulliken charge distribution showed that the carbonyl oxygen atom of the carboxylic group is more negative (~ - 0.4) as compared to other oxygen atoms (~ -0.3) in all selected compounds. Frontier molecular orbitals energy diagram and their bandgap provided indications about chemical reactivity and kinetic stability of the molecules. The synthesized compounds were tested for antifungal effects against Aspergillus niger and Candida albicans, which indicated that the compounds had good antifungal activity.

Steroidal pyrazolines as a promising scaffold in drug discovery

2020 ◽  
Vol 12 (10) ◽  
pp. 949-959
Author(s):  
Ranju Bansal ◽  
Ranjit Singh
Keyword(s):  
Drug Discovery ◽  
Broad Spectrum ◽  
Chemical Reactivity ◽  
Biological Activities ◽  
Antimicrobial Activities ◽  
Review Article ◽  
Pharmacological Activities ◽  
Neuroprotective Effects ◽  
Wide Range

Steroidal pyrazolines constitute an interesting and promising scaffold for drug discovery as they display diverse chemical reactivity and a wide range of biological activities. Literature reports indicate potent anticancer potential of steroidal pyrazolines along with broad-spectrum antimicrobial activities. Strong neuroprotective effects with steroids possessing pyrazoline moiety have also been observed. Among all the therapeutically active steroidal pyrazolines, D-ring-substituted derivatives are highly potent and the least toxic. The current and futuristic research approaches in this area are focused towards the exploration of this promising scaffold to develop molecules with widespread pharmacological activities. This review article mainly covers the synthetic and pharmacological aspects of steroidal pyrazolines, which will assist the medicinal chemists working in this area in their scientific endeavors.

scholarly journals Parachute structure trisiloxane surfactant: synthesis and its use in reverse flotation of iron ore

2021 ◽  
Author(s):  
Zhiqiang Huang ◽  
Shiyong Zhang ◽  
Vladimir E. Burov ◽  
Hongling Wang ◽  
Rukuan Liu ◽  
...  
Keyword(s):  
Density Functional ◽  
Chemical Reactivity ◽  
Froth Flotation ◽  
Density Functional Theory Calculations ◽  
Raw Material ◽  
Mulliken Charge ◽  
Single Element ◽  
Test Results ◽  
Functional Theory ◽  
Flotation Process

Abstract No single element has exerted such a deep influence on social organization of mankind as iron. Magnetite is concentrated by froth flotation and used as a raw material to produce iron. However, the conventional surfactants used in the flotation process often lead to the weak collecting performance due to their analogous alkyl hydrophobic group. Here, we report a new trisiloxane surfactant N-(β-aminoethyl)-γ-aminopropyltrisiloxane (AAT) in magnetite flotation, which was compared with the traditional collector dodecylamine (DA). The flotation test results showed that AAT had excellent collecting ability and selectivity for quartz against magnetite. Magnetite concentrate with TFe recovery of 84.79%, TFe grade of 68.84% and SiO2 grade of 6.15% was obtained by using 150 g/t AAT. Density functional theory calculations suggested reactive site of AAT was cationic –CH2N+H3 group, and AAT showed a higher positive grouping Mulliken charge and chemical reactivity that may promote its flotation performance.

scholarly journals A review on biological activities of Schiff base ligand and their metal complexes

2020 ◽  
Vol 13 (1) ◽  
pp. 217-221
Author(s):  
P.M. Jadhav
Keyword(s):  
Schiff Base ◽  
Metal Complexes ◽  
Schiff Bases ◽  
Carbonyl Compounds ◽  
Biological Activities ◽  
Condensation Reaction ◽  
Cytotoxic Activities ◽  
Wide Range ◽  
Enzymatic Agents ◽  
Dye Industry

Schiff bases and their metal complexes are wide range of biological applications and are synthesized from the condensation reaction of amino compounds with carbonyl compounds. Schiff base and their metal complexes have a wide variety of applications in food and dye industry, agrochemical, polymer, catalysis, analytical chemistry, antifertility, antiinflammatory activity, antiradical activity, and biological system as enzymatic agents. Several have reviewed them of their antimicrobial, antibacterial, antifungal, antitumor, and cytotoxic activities. This review summarized the most promising biological activities of Schiff bases and their metal complexes

scholarly journals New information of dopaminergic agents based on quantum chemistry calculations

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Guillermo Goode-Romero ◽  
Ulrika Winnberg ◽  
Laura Domínguez ◽  
Ilich A. Ibarra ◽  
Rubicelia Vargas ◽  
...  
Keyword(s):  
Density Functional ◽  
Clinical Decision Making ◽  
Chemical Reactivity ◽  
Density Functional Theory Calculations ◽  
Clinical Decision ◽  
Underlying Mechanism ◽  
New Information ◽  
Quantum Chemistry Calculations ◽  
Wide Range ◽  
Donor Acceptor

AbstractDopamine is an important neurotransmitter that plays a key role in a wide range of both locomotive and cognitive functions in humans. Disturbances on the dopaminergic system cause, among others, psychosis, Parkinson’s disease and Huntington’s disease. Antipsychotics are drugs that interact primarily with the dopamine receptors and are thus important for the control of psychosis and related disorders. These drugs function as agonists or antagonists and are classified as such in the literature. However, there is still much to learn about the underlying mechanism of action of these drugs. The goal of this investigation is to analyze the intrinsic chemical reactivity, more specifically, the electron donor–acceptor capacity of 217 molecules used as dopaminergic substances, particularly focusing on drugs used to treat psychosis. We analyzed 86 molecules categorized as agonists and 131 molecules classified as antagonists, applying Density Functional Theory calculations. Results show that most of the agonists are electron donors, as is dopamine, whereas most of the antagonists are electron acceptors. Therefore, a new characterization based on the electron transfer capacity is proposed in this study. This new classification can guide the clinical decision-making process based on the physiopathological knowledge of the dopaminergic diseases.

One-pot Synthesis of Betulin Triterpenoid Quaternized Pyridine Derivatives and their Antimicrobial Activity

2019 ◽  
Vol 17 (1) ◽  
pp. 79-84 ◽  
Author(s):  
Elvira Rifovna Shakurova ◽  
Darina Alexandrovna Pozdnyakova ◽  
Elena Valeryevna Tretyakova ◽  
Lyudmila Vyacheslavovna Parfenova
Keyword(s):  
Antifungal Activity ◽  
Biological Activities ◽  
Effective Interaction ◽  
Inhibition Zone ◽  
Pyridine Derivatives ◽  
One Pot ◽  
Biological Targets ◽  
Wide Range ◽  
Low Toxicity ◽  
Antibacterial And Antifungal

Background: A wide range of biological activity, relatively low toxicity and multiple pharmacological effects of triterpenoids are major advantages of these compounds in the prevention and treatment of various diseases. They include the lupane- type triterpenoids that proved to be a promising platform for the synthesis of analogs with a wide range of biological activities, including anti-inflammatory, antitumor, antiparasitic and antiviral properties. The main disadvantage complicating the use of all known derivatives of lupane acids in medical practice is low bioavailability associated with poor solubility in biologic fluids, limiting their effective interaction with the biological targets. Objective: The objective of this study is the synthesis of new amphiphilic betulin derivatives on the base of pyridinium salts with antifungal and antibacterial activity. Methods: In this study we have developed an effective one-pot method for the preparation of new quaternized pyridine derivatives 4-6 of the betulinic series based on the reaction of the initial triterpenes 1-3 with the Tempo+Br3 - reagent in the pyridine. The synthesized and initial compounds were tested for their antimicrobial and antifungal activity. Results: The data presented in this document indicate that all synthesized compounds 4-6 exhibited high activity against both gram-positive Staphylococcus aureus bacteria and gram-negative Pseudomonas aeruginosa strains, as well as Candida albicans and Cryptococcus neoformans fungi with the >90% coverage of the inhibition zone. The best result in a series of compounds 4-6 was found for the derivative 6 at the minimum inhibitory concentration of 1 µg/ml against S. aureus bacteria, C. albicans and C. neoformans fungi at the concentration of 8 µg/ml. Conclusion: Thus, we have demonstrated the first example of the pyridine quaternization using the betulin triterpenoids as the lipophilic substrates and Tempo+Br3 - cation. The obtained quaternized pyridine analogs of betulin triterpenes showed high antibacterial and antifungal activity in comparison with the initial compounds.

scholarly journals Germacrone: Occurrence, Synthesis, Chemical Transformations and Biological Properties

2008 ◽  
Vol 3 (4) ◽  
pp. 1934578X0800300 ◽  
Author(s):  
Alejandro F. Barrero ◽  
M. Mar Herrador ◽  
Pilar Arteaga ◽  
Julieta V. Catalán
Keyword(s):  
Essential Oils ◽  
Chemical Reactivity ◽  
Biological Activities ◽  
Biological Properties ◽  
Chemical Transformations ◽  
Cyclization Reactions ◽  
Cns Depressant ◽  
Complete Synthesis ◽  
Wide Range ◽  
Total Oil

Germacrone (1) forms part of a great number of essential oils, in some of them comprising more than 20% of the total oil. This compound presents a wide range of biological activities (CNS depressant, antiinflammatory, antiulcer, antifeedant, antibacterial, antifungal, antitumor, antitussive, vasodilator, choleretic, hepatoprotector), which are analyzed. The chemical reactivity of germacrone, including cyclization reactions, and complete synthesis are presented.

scholarly journals Theoretical Investigation on Biological Activity of Imidazole Derivatives [Carbenzim, Mebendazole] by using (DFT) and (PM3) Methods

2021 ◽  
Vol 24 (2) ◽  
pp. 1-8
Author(s):  
Amar Tuma Musa ◽  
◽  
Khalida Abaid ◽  
Keyword(s):  
Density Functional ◽  
Chemical Potential ◽  
Theoretical Study ◽  
Chemical Reactivity ◽  
Biological Activities ◽  
Biological Properties ◽  
Benzimidazole Derivatives ◽  
Log P ◽  
P Value ◽  
Reactivity Descriptors

The theoretical study represents an essential preliminary stage for the start of any industry, as it gives a theoretical description of the properties of compounds (chemical, physical and biological properties)without conducting research to find out about this and the least cost. Through the theoretical study, we extract a clear picture of the chemical compounds before starting to manufacture them to know the extent of their impact on human health and their chemical and biological effectiveness. Using the Density Functional Theory (DFT/B3LYP) with base 6-311G,throughGaussian 09 program, the optimize geometry,(bond lengths, angles bond)and vibrational spectra was calculated of the benzimidazole derivatives [Carbenzim (CZM), Mebendazole (MBZ)].Through orbital charts of HOMO and LUMO to study electronic properties. The HOMO-LUMO gap was also evaluated for chemical reactivity and determination of global reactivity descriptors (Hardness (),Softness (S), Electrophilicity(), Chemical potential(),Electronegativity(χ))] that defines compunds effectiveness and the their biological activities. In addition, (QSAR) data has been used to develop relationships between biological activities and thermophysical properties of chemicals, through the Hyper Chem8.0programbyusingSemi-empirical(SE)method at the (PM3) level. The LOG P value was calculated, binding energy, Polarizability, hydration energy, surface area, and electrostatic potential energy difference of two level.

scholarly journals 2-Aminobenzothiazole Containing Novel Schiff Bases Derivatives: Search for New Antibacterial Agents

2015 ◽  
Vol 53 ◽  
pp. 106-113 ◽  
Author(s):  
Manoj N. Bhoi ◽  
Mayuri A. Borad ◽  
Neha K. Panchal ◽  
Hitesh D. Patel
Keyword(s):  
Schiff Bases ◽  
Antibacterial Agents ◽  
Biological Activities ◽  
Gram Negative Bacteria ◽  
Significant Activity ◽  
Sequential Reaction ◽  
Wide Range ◽  
In Vitro Antibacterial Activity ◽  
Therapeutic Properties

The benzothiazole and Schiff base moieties are crucial functionalities due to their wide variety of biological activities and have a wide range of therapeutic properties. Keeping in view the importance of these organic moieties, a new series of 2-Aminobenzothiazole containing novel Schiff bases derivatives were synthesized by sequential reaction. The structures of the synthesized compounds were confirmed by their analytical and spectral data. The synthesized compounds were evaluated for their in vitro antibacterial activity against gram positive and gram negative bacteria. Synthesized compounds showed significant activity against microorganisms, which can be correlated with the privileged heterocyclic structural scaffolds.

scholarly journals The Inhibition of Non-albicans Candida Species and Uncommon Yeast Pathogens by Selected Essential Oils and Their Major Compounds

Molecules ◽  
2021 ◽  
Vol 26 (16) ◽  
pp. 4937
Author(s):  
Narcisa Mandras ◽  
Janira Roana ◽  
Daniela Scalas ◽  
Simonetta Del Re ◽  
Lorenza Cavallo ◽  
...  
Keyword(s):  
Antifungal Activity ◽  
Essential Oils ◽  
Candida Species ◽  
Fungal Infections ◽  
Biological Activities ◽  
Antifungal Drugs ◽  
Thymus Vulgaris ◽  
Foeniculum Vulgare ◽  
Lemon Balm ◽  
Wide Range

The epidemiology of yeast infections and resistance to available antifungal drugs are rapidly increasing, and non-albicans Candida species and rare yeast species are increasingly emerging as major opportunistic pathogens. In order to identify new strategies to counter the threat of antimicrobial resistant microorganisms, essential oils (EOs) have become an important potential in the treatment of fungal infections. EOs and their bioactive pure compounds have been found to exhibit a wide range of remarkable biological activities. We investigated the in vitro antifungal activity of nine commercial EOs such as Thymus vulgaris (thyme red), Origanum vulgare (oregano), Lavandula vera (lavender), Pinus sylvestris (pine), Foeniculum vulgare (fennel), Melissa officinalis (lemon balm), Salvia officinalis (sage), Eugenia caryophyllata (clove) and Pelargonium asperum (geranium), and some of their main components (α-pinene, carvacrol, citronellal, eugenol, γ-terpinene, linalool, linalylacetate, terpinen-4-ol, thymol) against non-albicans Candida strains and uncommon yeasts. The EOs were analyzed by GC-MS, and their antifungal properties were evaluated by minimum inhibitory concentration and minimum fungicidal concentration parameters, in accordance with CLSI guidelines, with some modifications for EOs. Pine exhibited strong antifungal activity against the selected non-albicans Candida isolates and uncommon yeasts. In addition, lemon balm EOs and α-pinene exhibited strong antifungal activity against the selected non-albicans Candida yeasts. Thymol inhibited the growth of all uncommon yeasts. These data showed a promising potential application of EOs as natural adjuvant for management of infections by emerging non-albicans Candida species and uncommon pathogenic yeasts.

scholarly journals Stabilising peroxyacids in niche microenvironments

2014 ◽  
Vol 70 (a1) ◽  
pp. C644-C644
Author(s):  
Dyanne Cruickshank ◽  
Chick Wilson
Keyword(s):  
Chemical Reactivity ◽  
Analytical Techniques ◽  
Direct Consequence ◽  
High Reactivity ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Wide Range ◽  
Chemically Reactive Species ◽  
Household Cleaning Products

There has been dramatic evolution in the formulation of household cleaning products over the last decade, this is mainly due to the influence of social change, regulatory pressure and the need for new less toxic, safer formulations with increased performance. Due to their high chemical reactivity, peroxides are found in a wide range of bleaching agents, they are known for their instability which is a direct consequence of their high reactivity (in turn essential for function). Stabilising such materials for implementation in a range of product types is a significant target within the domestic products industry. Supramolecular approaches are already being explored to try stabilise other chemically reactive species such as explosives [1,2] thus illustrating the feasibility of this research. The work to be presented will deal with peroxyacids that include small model compounds such as m-chloroperbenzoic acid as well as a commericially relevant bleaching agent and their inclusion in both crystalline and amorphous hosting systems. Single crystal X-ray diffraction methods are used to elucidate the ordered crystalline structures and to confirm whether or not the peroxo group is still intact within the crystalline host environments. Simple reactivity tests are used to demonstrate whether or not the amorphous host-guest complexes contain the active peroxy acid within their host cavity. Other complementary analytical techniques such as powder X-ray diffraction, differential scanning calorimetry and thermogravimetry have also been used to characterise the newly-hosted peroxyacid materials. By hosting these molecules in microenvironments it is possible to prepare formulations that are less pH sensitive, thus making their storage safer while allowing their reactivity to be controlled and tuned.

Sign in / Sign up

Export Citation Format

Share Document