Efficacy of Albizia malacophylla (A.Rich.) Walp. (Leguminosae) methanol (80%) leaf extract and solvent fractions against Plasmodium berghei-induced malaria in mice model

ETHNOPHARMACOLOGICAL RELEVANCE

Novel drugs are needed to address the issue of malarial infection resistance; natural items can be a different source of these medications. Albizia malacophylla (A. Rich.) Walp. (Leguminosae) is listed as one of the antimalarial medicinal plants in Ethiopian folk medicine. However, there are no reports regarding the biological activity or phytochemistry of the plant.

AIM OF THE STUDY

Thus, this study aimed to evaluate the A. malacophylla crude extract and solvent fractions' in vivo antimalarial activity utilizing 4-day suppressive, preventative, and curative tests in mice infected with P. berghei.

MATERIALS AND METHODS

The parasite Plasmodium berghei, which causes rodent malaria, was used to infect healthy male Swiss Albino mice, weighing 23-28 g and aged 6-8 weeks. Solvent fractions such as methanol, water, and chloroform were given in addition to an 80% methanolic extract at 100, 200, and 400 mg/kg doses. A Conventional test such as parasitemia, survival time, body weight, temperature, and packed cell capacity were employed to ascertain factors such as the suppressive, curative, and preventive tests.

RESULTS

Every test substance dramatically reduced the number of parasites in every experiment. Crude extract (with the highest percentage suppression of 67.78%) performs better antimalarial effect than the methanol fraction, which is the most efficient solvent fraction with a percentage suppression of 55.74%. With a suppression value of 64.83% parasitemia level, the therapeutic effects of 80% methanolic crude extract were greater than its curative and preventative effects in a four-day suppressive test. The survival period (17 days) was longer with the hydroalcoholic crude extract dose of 400 mg/kg than with other doses of the materials under investigation.

CONCLUSIONS

The results of this investigation validate the antimalarial characteristics of A. malacophylla leaf extract. The crude extract prevented weight loss, a decline in temperature, and a reduction in PCV. The results demonstrate that the plant has a promising antimalarial effect against P. berghei, hence supporting the traditional use of the plant. Therefore, it could serve as a foundation for the development of new antimalarial drugs.

New lignan glycosides from Justicia secunda Vahl (Acanthaceae) with antimicrobial and antiparasitic properties

Three new lignan glucosides, namely, justisecundosides A (1), B (2a), and C (2b), were isolated from the whole plant of Justicia secunda together with seven known compounds (3-9). Their structures were established based on a comprehensive analysis of HR-ESI-MS, IR, UV, and CD, in conjunction with their 1D and 2D-NMR data. A putative biogenetic pathway of compounds 1-2a,b from coniferyl alcohol was proposed. In addition, the antimicrobialactivities of the extract, fractions, and some isolated compounds were assessed against multiresistant bacterial and fungal strains. Furthermore, the antiplasmodial, antileishmanial, and antitrypanosomal activities were assessed against the sensitive (3D7) and multidrug-resistant (Dd2) strains of P. falciparum, promastigote and bloodstream forms of L. donovani, and Trypanosoma brucei, respectively. Compound 4 exhibited moderate antibacterial activity against Staphylococcus aureus SA RN 46003 with a MIC value of 62.5 μg/mL. Besides, compound 6 demonstrated a very good activity against sensitive (IC50Pf3D7: 0.81 μg/mL) and multidrug-resistant (IC50PfDd2: 14.61 μg/mL) strains of P. falciparum while compound 4 displayed good antitrypanosomal activity (IC50: 1.19 μg/mL). Also, compound 1 was the most active on the promastigote form of L. donovani with an IC50 of 13.02 μg/mL.

Antimalarial potential of Moringa oleifera Lam. (Moringaceae): A review of the ethnomedicinal, pharmacological, toxicological, and phytochemical evidence

Several regions of the world frequently use the species Moringa oleifera Lam. (Moringaceae) in traditional medicine. This situation is even more common in African countries. Many literature reports point to the antimalarial potential of this species, indicating the efficacy of its chemical compounds against malaria-causing parasites of the genus Plasmodium. From this perspective, the present study reviews the ethnobotanical, pharmacological, toxicological, and phytochemical (flavonoids) evidence of M. oleifera, focusing on the treatment of malaria. Scientific articles were retrieved from Google Scholar, PubMed^®, ScienceDirect^®, and SciELO databases. Only articles published between 2002 and 2022 were selected. After applying the inclusion and exclusion criteria, this review used a total of 72 articles. These documents mention a large use of M. oleifera for the treatment of malaria in African and Asian countries. The leaves (63%) of this plant are the main parts used in the preparation of herbal medicines. The in vivo antimalarial activity of M. oleifera was confirmed through several studies using polar and nonpolar extracts, fractions obtained from the extracts, infusion, pellets, and oils obtained from this plant and tested in rodents infected by the following parasites of the genus Plasmodium: P. berghei, P. falciparum, P. yoelii, and P. chabaudi. Extracts obtained from M. oleifera showed no toxicity in preclinical tests. A total of 46 flavonoids were identified in the leaves and seeds of M. oleifera by different chromatography and mass spectrometry methods. Despite the scarcity of research on the antimalarial potential of compounds isolated from M. oleifera, the positive effects against malaria-causing parasites in previous studies are likely to correlate with the flavonoids that occur in this species.

Antimalarial activity of the 80%methanol extract and solvent fractions of Cucumis ficifolius A. rich roots against Plasmodium berghei in mice

Ethnopharmacological relevance

Malaria is still a known health threat, especially in parts of sub-Saharan Africa. It is one of the frequently mentioned issues with hospital admission and outpatient care in Ethiopia. Cucumis ficifolius A. Rich roots are historically used in Ethiopia to treat meningitis, inflammation, and malaria. However, the antimalarial activity of this plant has not been scientifically studied so far.

Aim of the study

This study aimed to determine the in vivo antimalarial activity of 80% methanol extract and solvent fractions of the roots of Cucumis ficifolius against Plasmodium berghei infection in mice.

Methods

The in vivo antimalarial activity of the 80% methanol extract and solvent fractions of Cucumis ficifolius A. Rich was evaluated by standard chemo suppressive, curative and repository tests using Plasmodium berghei (ANKA strain) in Swiss albino mice at doses of 100, 200 and 400 mg/kg/day. The level of parasitemia, survival time, variation in weight, rectal temperature, and packed cell volume of mice were determined to establish the activity of the extracts.

Result

The 80% methanol extract of Cucumis ficifolius A. Rich roots had a promising suppression of parasitemia at 400 mg/kg with a chemosuppression value of 65.21 ± 1.20%. Among the solvent fractions, the chloroform fraction showed the highest antimalarial activity in the four-day suppressive test with a chemosuppression value of 55.9 ± 0.28%, followed by the n-butanol (42.9 ± 0.24%), and aqueous (40.57 ± 0.52%) fractions at a dose of 400 mg/kg. The highest survival times were observed with crude extract (15.4 ± 0.24 days) at 400 mg/kg, and chloroform fraction (13.4 + 0.24 days), though all extracts increased survival time.

Conclusion

The findings of the present study collectively indicate the root extract of Cucumis ficifolius has a promising antiplasmodial activity which substantiates the traditional claim of the plant.

Design, synthesis, characterization and anticancer activity evaluation of deoxycholic acid-chalcone conjugates

A series of deoxycholic acid-chalcone amides were synthesised and tested against the human lung cancer cell line, A549 and the cervical cancer cell line, SiHa. Among the synthesised deoxycholic acid-chalcone conjugates, some conjugates showed encouraging results as anticancer agents with good in vitro activity. More precisely, deoxycholic acid-chalcone conjugates 4b (IC50: 0.51 μM) and 4e (IC50: 0.84 μM) having 2‑nitrophenyl and 3,4,5‑trimethoxyphenyl groups exhibited a good activity against human cancer cell-line SiHa and while 4d (IC50: 0.25 μM) and 4b (IC50: 1.71 μM) showed better activity against A549 lung cancer cell line with respect to deoxycholic acid and chalcones. The anticancer activity of the bile acid conjugated chalcones was more than the activity of chalcone and deoxycholic acid alone. The results indicate that a bile acid conjugate strategy may be beneficial in improving the biological activity of chalcone derivatives. The enhanced activity of certain compounds may be due to their increased bioavailability.

Characterization, molecular modeling and pharmacology of some 2́-hydroxychalcone derivatives as SARS-CoV-2 inhibitor

This work presented the microwave assisted synthesis of six new 2́-hydroxychalcones and their characterization based on FTIR, UV-Vis, ¹H NMR, and mass spectral analysis. Quantum chemical studies confirmed the structures of prepared chalcones. Antioxidant, in vitro antimicrobial and in silico antiviral studies have been performed to evaluate their biological performance. Results of molecular docking of prepared 2́-hydroxychalcones against SARS-CoV-2 (7BQY) main protease disclosed their inhibition which is comparable to standard, remdesivir and better than hydroxychloroquine (HCQ). ADMET prediction revealed them to be non-carcinogenic and relatively safe.

Evaluation of Antimalarial Activity of 80% Methanolic Root Extract of Dorstenia barnimiana Against Plasmodium berghei-Infected Mice

BACKGROUND

Due to resistance of parasites, costs, and safety issues with currently available drugs, there is a need to discover new antimalarials. Medicinal plants are one of the most important sources of new drugs. The purpose of this study was to evaluate the antimalarial activity of a methanolic root extract of Dorstenia barnimiana in Swiss albino mice infected with Plasmodium berghei.

METHODS

Four-day suppressive, curative, and prophylactic tests were performed on mice infected with P. berghei to evaluate the antimalarial activity of a methanolic root extract of the plant. Parasitemia suppression, survival time, body-weight change, rectal temperature change, and packed-cell volume were used to evaluate the activity of the extract. Data were analyzed using one-way ANOVA followed by Tukey's post hoc test for comparisons between and within groups, with P<0.05 considered statistically significant.

RESULTS

The D. barnimiana root extract showed significant (P<0.01) parasitemia-suppressive activities in all models compared to the negative control. The extract increased mean survival time and prevented weight loss, reduction in temperature, and anemia significantly in all tested doses in 4-day suppressive and curative tests.

CONCLUSION

Based on these findings, D. barnimiana root has promising antimalarial activity and can considered a potential source to develop new agents.

Phytochemical and Antimalarial Effects of Ecballium elaterium (L.) Rich. Growing in Iran

Background: Malaria is a well-recognized parasitic disease and a serious public health problem worldwide, particularly in tropical and subtropical areas. Objectives: This study was conducted to investigate the antimalarial properties of extracts with different polarities from the various parts of Ecballium elaterium (L.) Rich. (or wild cucumber) as a perennial herbaceous plant growing in Gilan and Azerbaijan provinces of Iran. Methods: The air-dried and powdered fruits, seeds, and roots of E. elaterium were extracted using three solvents with different polarities, n-Hexane (n-Hex), dichloromethane (DCM), and methanol (MeOH). The MeOH extract of roots was subjected to fractionalizing by a C18 Sep-Pak cartridge. All extracts and fractions with different polarities were assessed for their antimalarial activity using the cell-free beta-hematin formation test, and the structural groups of the fractions were identified by Thin-Layer Chromatography (TLC). Results: According to our results, the MeOH extracts of the plant’s roots presented considerable antimalarial effects with an IC50 value of 0.124 ± 0.0002 mg/mL. Bioactivity-guided fractionation of root MeOH extract by solid phase extraction (SPE) afforded six fractions. The 20% fraction showed the most potent antimalarial effect with an IC50 value of 0.167 ± 0.002 mg/mL. Moreover, the three fractions of 80%, 60%, and 100% methanol/water demonstrated considerable antimalarial activities. Phytochemical analysis of potent fractions of E. elaterium suggested the presence of flavonoids in 20% and 60% fractions and flavonoids and triterpenoids in 80% and 100% fractions. Conclusions: According to our primary phytochemical investigation on the six SPE fractions, it is recommended to purify the active constituents of the most effective fractions and investigate their biological effects in animal models.

Synthesis, Biological Evaluation and Molecular Docking Studies of New Pyrazolines as an Antitubercular and Cytotoxic Agents

BACKGROUND

Many synthetic procedures were reported till date to prepare pyrazoline derivatives. Some have published pyrazolines from different chalcone derivatives in the literature.

OBJECTIVE

A series of new pyrazolines containing novel 2,5-dichloro-3-acetylthiophene chalcone moiety (PZT1-PZT20) have been synthesized, characterized by 1HNMR and 13CNMR and evaluated for them in vitro antitubercular activity against M. tuberculosis H37Rv strain and in vitro anticancer activity against DU-145 prostate cancer cell lines and all compounds were also screened for molecular docking studies against specific targeted protein domains.

METHODS

All compounds were screened for potential activity against Mycobacterium tuberculosis H37Rv (MTB) strain and anticancer activity against DU-149 prostate cancer cell lines using MTT cytotoxicity assay.

RESULTS

Among the series, compound PZT5 with 2", 4"-dichlorophenyl group at 5-position on the pyrazoline ring exhibited the most potent antitubercular activity (MIC=1.60 µg/mL) and compounds PZT2, PZT9, PZT11, PZT15, and PZT20 showed similar antitubercular activity against standard pyrazinamide (MIC=3.12 µg/mL) by broth dilution assay. PZT15 and PZT17 with 4"- pyridinyl and 2"-pyrrolyl groups on pyrazoline ring were found to exhibit better anticancer activity against DU-149 prostate cancer cell lines with IC50 values of 2.0±0.2 µg/mL and 6.0±0.3 µg/mL respectively by MTT assay. The preliminary structure-activity relationship has been summarized. The molecular docking studies with crystalline structures of enoyl acyl carrier protein reductase InhA interaction with target protein (2NSD; PDB and 3FNG; PDB) of Mycobacterium tuberculosis H37Rv (MTB) strain have also exhibited good ligand interaction and binding affinity. Ligand interaction and binding affinity were estimated using crystal structures of both types of enoyl acyl carrier protein reductase InhA (3FNG.pdb) and found to be much higher (-16.70 to - 19.20 kcal/mol) compared with pyrazinamide (-10.70 kcal/mol) as a standard target molecule. Whereas the binding affinities of six active compounds with crystal structure of other type of enoyl acyl carrier protein reductase InhA (2NSD.pdb) were much similar and higher (-9.30 to - 11.20 kcal/mole) than pyrazinamide (-11.10 kcal/mole).

CONCLUSION

These new pyrazolines would be promising potent inhibitors of drug sensitive and drug resistant Mycobacterium tuberculosis strain and potential anticancer agents against prostate cancer and other prototypes of cancers.

In vitro anti-malarial efficacy of chalcones: cytotoxicity profile, mechanism of action and their effect on erythrocytes

BACKGROUND

Malaria extensively leads to mortality and morbidity in endemic regions, and the emergence of drug resistant parasites is alarming. Plant derived synthetic pharmaceutical compounds are found to be a foremost research to obtain diverse range of potent leads. Amongst them, the chalcone scaffold is a functional template for drug discovery. The present study involves synthesis of ten chalcones with various substitution pattern in rings A and B and assessment of their anti-malarial efficacy against chloroquine sensitive and chloroquine resistant strains as well as of their cytotoxicity and effect on haemozoin production.

METHODS

The chalcones were synthesized by Claisen-Schmidt condensation between equimolar quantities of substituted acetophenones and aryl benzaldehydes (or indole-3-carboxaldehyde) and were screened for anti-malarial activity by WHO Mark III schizont maturation inhibition assay. The cytotoxicity profile of a HeLa cell line was evaluated through MTT viability assay and the selectivity index (SI) was calculated. Haemozoin inhibition assay was performed to illustrate mode of action on a Plasmodium falciparum strain.

RESULTS

The IC₅₀ values of all compounds were in the range 0.10-0.40 μg/mL for MRC-2 (a chloroquine sensitive strain) and 0.14-0.55 μg/mL for RKL-9 (a chloroquine resistant strain) of P. falciparum. All the chalcones showed low cellular toxicity with minimal haemolysis. The statistically significant reduction (p < 0.05) in the haemozoin production suggests a similar mechanism than that of chloroquine.

CONCLUSIONS

Out of ten chalcones, number 7 was found to be a lead compound with the highest potency (IC₅₀ = 0.11 µg/mL), as compared to licochalcone (IC₅₀ = 1.43 µg/mL) and with high selectivity index of 85.05.

Extracts Obtained from Pterocarpus angolensis DC and Ziziphus mucronata Exhibit Antiplasmodial Activity and Inhibit Heat Shock Protein 70 (Hsp70) Function

Malaria parasites are increasingly becoming resistant to currently used antimalarial therapies, therefore there is an urgent need to expand the arsenal of alternative antimalarial drugs. In addition, it is also important to identify novel antimalarial drug targets. In the current study, extracts of two plants, Pterocarpus angolensis and Ziziphus mucronata were obtained and their antimalarial functions were investigated. Furthermore, we explored the capability of the extracts to inhibit Plasmodium falciparum heat shock protein 70 (Hsp70) function. Heat shock protein 70 (Hsp70) are molecular chaperones whose function is to facilitate protein folding. Plasmodium falciparum the main agent of malaria, expresses two cytosol-localized Hsp70s: PfHsp70-1 and PfHsp70-z. The PfHsp70-z has been reported to be essential for parasite survival, while inhibition of PfHsp70-1 function leads to parasite death. Hence both PfHsp70-1 and PfHsp70-z are potential antimalarial drug targets. Extracts of P. angolensis and Z. mucronata inhibited the basal ATPase and chaperone functions of the two parasite Hsp70s. Furthermore, fractions of P. angolensis and Z. mucronata inhibited P. falciparum 3D7 parasite growth in vitro. The extracts obtained in the current study exhibited antiplasmodial activity as they killed P. falciparum parasites maintained in vitro. In addition, the findings further suggest that some of the compounds in P. angolensis and Z. mucronata may target parasite Hsp70 function.

Synthesis, antimalarial activity in vitro, and docking studies of novel neolignan derivatives

The absence of effective vaccines against malaria and the difficulties associated with controlling mosquito vectors have left chemotherapy as the primary control measure against malaria. However, the emergence and spread of parasite resistance to conventional antimalarial drugs result in a worrisome scenario making the search for new drugs a priority. In the present study, the activities of nine neolignan derivatives were evaluated as follows: (i) against blood forms of chloroquine-resistant Plasmodium falciparum (clone W2), using the tritiated hypoxanthine incorporation and anti-HRPII assays; (ii) for cytotoxic activity against cultured human hepatoma cells (HepG2); and (iii) for intermolecular interaction with the P. falciparum cysteine protease of falcipain-2 (F2) by molecular docking. The neolignan derivatives 9 and 10 showed activity against the blood form of the chloroquine-resistant P. falciparum clone W2 and were not cytotoxic against cultured human hepatoma cells. A molecular docking study of these two neolignans with FP2 revealed several intermolecular interactions that should guide the design of future analogs.

Design, in silico and in vitro evaluation of curcumin analogues against Plasmodium falciparum

The polyphenolic compound curcumin has been reported for its antimalarial properties in various scientific studies. Plasmodium falciparum ATP6, the parasite orthologue of mammalian sarcoplasmic Ca²⁺ ATPase (SERCA) has been identified as a key molecular target of both artemisinin and curcumin. The work was thereby undertaken to study the anti-malarial properties of two different series of curcumin analogues based on their docking interactions with PfATP6 and correlating the results with their anti-malarial activity. The compounds were designed retaining similar functional groups as that of the parent curcumin nucleus while incorporating changes in the carbon chain length, unsaturated groups and the number of ketone groups. The compounds (1E, 4E)-1,5-bis(4-methylphenyl)penta-1,4-dien-3-one (CD-9), (1E, 4E)-1,5-bis(4-methoxyphenyl)penta-1,4-dien-3-one (CD-8) and (E)-1,3-bis(4-hydroxylphenyl)prop-2-en-1-one (CD-1) showed IC₅₀ values of 1.642 μM, 1.764 μM and 2.59 μM in 3D7 strain and 3.039 μM, 7.40 μM and 11.3 μM in RKL-2 strain respectively. Detailed structure-activity relationship studies of the compounds showed that CD-9 and CD-8 had a common hydrophobic interaction with the residue Leu268 of the PfATP6 protein and has been postulated through our study to be the reason for their antimalarial activity as seen after corroborating the results with the in vitro study. The study provided valuable insight about the ligand-protein interaction of the various functional groups of curcumin and its analogues against the PfATP6 protein and their importance in imparting antimalarial action.

Novel Halogenated Pyrazine-Based Chalcones as Potential Antimicrobial Drugs

Chalcones, i.e., compounds with the chemical pattern of 1,3-diphenylprop-2-en-1-ones, exert a wide range of bio-activities, e.g., antioxidant, anti-inflammatory, anticancer, anti-infective etc. Our research group has been focused on pyrazine analogues of chalcones; several series have been synthesized and tested in vitro on antifungal and antimycobacterial activity. The highest potency was exhibited by derivatives with electron withdrawing groups (EWG) in positions 2 and 4 of the ring B. As halogens also have electron withdrawing properties, novel halogenated derivatives were prepared by Claisen-Schmidt condensation. All compounds were submitted for evaluation of their antifungal and antibacterial activity, including their antimycobacterial effect. In the antifungal assay against eight strains of selected fungi, growth inhibition of Candida glabrata and Trichophyton interdigitale (formerly T. mentagrophytes) was shown by non-alkylated derivatives with 2-bromo or 2-chloro substitution. In the panel of selected bacteria, 2-chloro derivatives showed the highest inhibitory effect on Staphylococcus sp. In addition, all products were also screened for their antimycobacterial activity against Mycobacterium tuberculosis H37RV My 331/88, M. kansasii My 235/80, M. avium 152/80 and M. smegmatis CCM 4622. Some of the examined compounds, inhibited growth of M. kansasii and M. smegmatis with minimum inhibitory concentrations (MICs) comparable with those of isoniazid.

In Silico Investigation of Flavonoids as Potential Trypanosomal Nucleoside Hydrolase Inhibitors

Human African Trypanosomiasis is endemic to 37 countries of sub-Saharan Africa. It is caused by two related species of Trypanosoma brucei. Current therapies suffer from resistance and public accessibility of expensive medicines. Finding safer and effective therapies of natural origin is being extensively explored worldwide. Pentamidine is the only available therapy for inhibiting the P2 adenosine transporter involved in the purine salvage pathway of the trypanosomatids. The objective of the present study is to use computational studies for the investigation of the probable trypanocidal mechanism of flavonoids. Docking experiments were carried out on eight flavonoids of varying level of hydroxylation, namely, flavone, 5-hydroxyflavone, 7-hydroxyflavone, chrysin, apigenin, kaempferol, fisetin, and quercetin. Using AutoDock 4.2, these compounds were tested for their affinity towards inosine-adenosine-guanosine nucleoside hydrolase and the inosine-guanosine nucleoside hydrolase, the major enzymes of the purine salvage pathway. Our results showed that all of the eight tested flavonoids showed high affinities for both hydrolases (lowest free binding energy ranging from −10.23 to −7.14 kcal/mol). These compounds, especially the hydroxylated derivatives, could be further studied as potential inhibitors of the nucleoside hydrolases.

Identification of novel phenyl butenonyl C-glycosides with ureidyl and sulfonamidyl moieties as antimalarial agents

A new series of C-linked phenyl butenonyl glycosides bearing ureidyl(thioureidyl) and sulfonamidyl moieties in the phenyl rings were designed, synthesized, and evaluated for their in vitro antimalarial activities against Plasmodium falciparum 3D7 (CQ sensitive) and K1 (CQ resistant) strains. Among all the compounds screened the C-linked phenyl butenonyl glycosides bearing sulfonamidyl moiety (5a) and ureidyl moiety in the phenyl ring (7d and 8c) showed promising antimalarial activities against both 3D7 and K1 strains with IC50 values in micromolar range and low cytotoxicity offering new HITS for further exploration.

One-pot diastreoselective synthesis of highly functionalized cyclohexenones: 2-oxo-N,4,6-triarylcyclohex-3-enecarboxamides

A series of 2-oxo-N,4,6-triarylcyclohex-3-enecarboxamides were synthesized by condensing acetophenone and aromatic aldehydes with acetoacetanilide in ethanol in the presence of 2-hydroxyethylammonium acetate (2-HEAA) as a basic ionic liquid at ambient conditions. This process is simple, efficient and environmentally benign and proceeds in high yield, short reaction times and there is no need for column chromatography purification.

Potential activity of 3-(2-chlorophenyl)-1-phenyl-propenonein accelerating wound healing in rats

Wound healing involves inflammation followed by granular tissue development and scar formation. In this study, synthetic chalcone 3-(2-Chlorophenyl)-1-phenyl-propenone (CPPP) was investigated for a potential role in enhancing wound healing and closure. Twenty-four male rats were divided randomly into 4 groups: carboxymethyl cellulose (CMC) (0.2 mL), Intrasite gel, and CPPP (25 or 50 mg/mL). Gross morphology, wounds treatment with the CPPP, and Intrasite gel accelerate the rate of wound healing compared to CMC group. Ten days after surgery, the animals were sacrificed. Histological assessment revealed that the wounds treated with CPPP showed that wound closure site contained little amount of scar and the granulation tissue contained more collagen and less inflammatory cells than wound treated with CMC. This finding was confirmed with Masson's trichrome staining. The antioxidant defence enzymes catalase (CAT) and superoxide dismutase (SOD) were significantly increased in the wound homogenates treated with CPPP (P < 0.05) compared to CMC treated group. However, in the CPPP treatment group, lipid peroxidation (MDA) was significantly decreased (P < 0.05), suggesting that the CPPP also has an important role in protection against lipid peroxidation-induced skin injury after ten days of treatment with CPPP, which is similar to the values of cytokines TGF-β and TNF-α in tissue homogenate. Finally the administration of CPPP at a dosage of 25 and 50 mg/kg was suitable for the stimulation of wound healing.

Flavones as isosteres of 4(1H)-quinolones: discovery of ligand efficient and dual stage antimalarial lead compounds

Malaria is responsible for nearly one million deaths annually, and the increasing prevalence of multi-resistant strains of Plasmodium falciparum poses a great challenge to controlling the disease. A diverse set of flavones, isosteric to 4(1H)-quinolones, were prepared and profiled for their antiplasmodial activity against the blood stage of P. falciparum W2 strain, and the liver stage of the rodent parasite Plasmodium berghei. Ligand efficient leads were identified as dual stage antimalarials, suggesting that scaffold optimization may afford potent antiplasmodial compounds.

Theoretical study on the antioxidant properties of 2'-hydroxychalcones: H-atom vs. electron transfer mechanism

The free radical scavenging activity of six 2'-hydroxychalcones has been studied in gas phase and solvents using the density functional theory (DFT) method. The three main working mechanisms, hydrogen atom transfer (HAT), stepwise electron-transfer-proton-transfer (ET-PT) and sequential-proton-loss-electron-transfer (SPLET) have been considered. The O-H bond dissociation enthalpy (BDE), ionization potential (IP), proton affinity (PA) and electron transfer energy (ETE) parameters have been computed in gas phase and solvents. The theoretical results confirmed the important role of the B ring in the antioxidant properties of hydroxychalcones. In addition, the calculated results matched well with experimental values. The results suggested that HAT would be the most favorable mechanism for explaining the radical-scavenging activity of hydroxychalcone in gas phase, whereas SPLET mechanism is thermodynamically preferred pathway in aqueous solution.

Molecular structure, spectral studies, intra and intermolecular interactions analyses in a novel ethyl 4-[3-(2-chloro-phenyl)-acryloyl]-3,5-dimethyl-1H-pyrrole-2-carboxylate and its dimer: A combined DFT and AIM approach

A newly synthesized chalcone, Ethyl 4-[3-(2-chloro-phenyl)-acryloyl]-3,5-dimethyl-1H-pyrrole-2-carboxylate (ECPADMPC) has been characterized by (1)H NMR, (13)C NMR, UV-Vis, FT-IR, Mass spectroscopy and elemental analysis. Quantum chemical calculations have been performed by DFT level of theory using B3LYP functional and 6-31G(d,p) as basis set. The time dependent density functional theory (TD-DFT) is used to find the various electronic transitions within molecule. A combined theoretical and experimental wavenumber analysis confirms the existence of dimer. Topological parameters-electron density (ρ(BCP)), Laplacian of electron density (∇(2)ρ(BCP)), energetic parameters-kinetic electron energy density (G(BCP)), potential electron density (V(BCP)) and the total electron energy density (H(BCP)) at the bond critical points (BCP) have been analyzed by 'Atoms in molecules' AIM theory in detail. The intermolecular hydrogen bond energy of dimer is calculated as -12.3kcal/mol using AIM calculations. AIM ellipticity analysis is carried out to confirm the presence of resonance assisted intermolecular hydrogen bonds in stabilization of dimer. The analysis clearly depicts the presence of different kind of interactions in dimer. This dimer may work as model system to understand the H-bonding interaction in biomolecules. The local reactivity descriptor analysis is performed to find the reactive sites within molecule.