Norizan Ahmat

Medicinal property, phytochemistry and pharmacology of several Jatropha species (Euphorbiaceae): A review

The genus Jatropha (Euphorbiaceae) comprises of about 170 species of woody trees, shrubs, subshrubs or herbs in the seasonally dry tropics of the Old and the New World. They are used in medicinal folklore to cure various diseases of 80% of the human population in Africa, Asia and Latin America. Species from this genus have been popular to cure stomachache, toothache, swelling, inflammation, leprosy, dysentery, dyscrasia, vertigo, anemia, diabetis, as well as to treat HIV and tumor, opthalmia, ringworm, ulcers, malaria, skin diseases, bronchitis, asthma and as an aphrodisiac. They are also employed as ornamental plants and energy crops. Cyclic peptides alkaloids, diterpenes and miscellaneous compounds have been reported from this genus. Extracts and pure compounds of plants from this genus are reported for cytotoxicity, tumor-promoting, antimicrobial, antiprotozoal, anticoagulant, immunomodulating, anti-inflammatory, antioxidant, protoscolicidal, insecticidal, molluscicidal, inhibition AChE and toxicity activities.

Malaysianol A, a new trimer resveratrol oligomer from the stem bark of Dryobalanops aromatica

A new resveratrol trimer, malaysianol A (1), five known resveratrol oligomers: laevifonol (2), ampelopsin E (3), α-viniferin (4), ε-viniferin (5), diptoindonesin A (6), and bergenin (7) have been isolated from the acetone extract of the stem bark of Dryobalanops aromatica by combination of vacuum and radial chromatography techniques. Their structures were established on the basis of their spectroscopic evidence and comparison with the published data. The cytotoxic activity of the compounds was tested against several cell lines in which compound 4 was found to inhibit strongly the growth of HL-60 cell line.

Novel 2,5-disubtituted-1,3,4-oxadiazoles with benzimidazole backbone: A new class of β-glucuronidase inhibitors and in silico studies

A library of novel 2,5-disubtituted-1,3,4-oxadiazoles with benzimidazole backbone (3a-3r) was synthesized and evaluated for their potential as β-glucuronidase inhibitors. Several compounds such as 3a-3d, 3e-3j, 3l-3o, 3q and 3r showed excellent inhibitory potentials much better than the standard (IC50=48.4±1.25μM: d-saccharic acid 1,4-lactone). All the synthesized compounds were characterized satisfactorily by using different spectroscopic methods. We further evaluated the interaction of the active compounds and the enzyme active site with the help of docking studies.

Benzimidazole derivatives as new α-glucosidase inhibitors and in silico studies.

Newly synthesized benzimidazole hydrazone derivatives 1-26 were evaluated for their α-glucosidase inhibitory activity. Compounds 1-26 exhibited varying degrees of yeast α-glucosidase inhibitory activity with IC50 values between 8.40 ± 0.76 and 179.71 ± 1.11 μM when compared with standard acarbose. In this assay, seven compounds that showed highest inhibitory effects than the rest of benzimidazole series were identified. All the synthesized compounds were characterized by different spectroscopic methods adequately. We further evaluated the interaction of the active compounds with enzyme with the help of docking studies.

Synthesis, crystal structure, DFT studies and evaluation of the antioxidant activity of 3,4-dimethoxybenzenamine schiff bases.

Schiff bases of 3,4-dimethoxybenzenamine 1–25 were synthesized and evaluated for their antioxidant activity. All the synthesized compounds were characterized by various spectroscopic techniques. In addition, the characterizations of compounds 13, 15 and 16 were supported by crystal X-ray determinations and their geometrical parameters were compared with theoretical DFT calculations at the B3LYP level of theory. Furthermore, the X-ray crystal data of two non-crystalline compounds 8 and 18 were theoretically calculated and compared with the practical values of compounds 13, 15, 16 and found a good agreement. The compounds showed good DPPH scavenging activity ranging from 10.12 to 84.34 μM where compounds 1–4 and 6 showed stronger activity than the standard n-propyl gallate. For the superoxide anion radical assay, compounds 1–3 showed better activity than the standard.

Malaysianol B, an oligostilbenoid derivative from Dryobalanops lanceolata

A new oligostilbenoid tetramer, malaysianol B (1), was isolated from the acetone extract of the stem bark of Dryobalanops lanceolata along with seven oligostilbenoids tetramers; hopeaphenol (2), stenophyllol A (3), nepalensinol B (4), vaticanol B (5) and C (6), upunaphenol D (7), and flexuosol A (8). The structures of the isolated compounds were established on the basis of their spectroscopic data evidence. The antibacterial activity of the isolated compounds was evaluated using resazurin microtitre-plate assay.

Synthesis, in vitro evaluation and molecular docking studies of biscoumarin thiourea as a new inhibitor of α-glucosidases

Biscoumarin analogs 1-18 have been synthesized, characterized by EI-MS and (1)H NMR and evaluated for α-glucosidase inhibitory potential. All compounds showed variety of α-glucosidase inhibitory potential ranging in between 13.5±0.39 and 104.62±0.3μM when compared with standard acarbose having IC50 value 774.5±1.94μM. The binding interactions of the most active analogs were confirmed through molecular docking. The compounds showed very good interactions with enzyme. All synthesized compounds 1-18 are new. Our synthesized compounds can further be studied to developed lead compounds.

A review of the medicinal uses, phytochemistry and pharmacology of the genus Sapium.

ETHNOPHARMACOLOGICAL RELEVANCE Several species from the genus Sapium possess a broad range of medicinal properties and they have been used as traditional medicines by indigenous groups in several regions such as Malaysia, Africa, Southern China and Bolivia. Most of the species reported to possess therapeutic effects which are used for the treatment of skin-related diseases such as eczema and dermatitis, but they may also be used for overstrain, lumbago, constipation and hernia. Species of this genus are also used to treat wounds and snake bites. In addition, the saps/latex of Sapium glandulosum, Sapium indicum and Sapium sebiferum have/has toxic effects and are used as bird and fish poisons. This review discusses the current knowledge of the medicinal uses, phytochemistry, biological activities and toxicities of species from the genus Sapium to reveal their therapeutic potentials and gaps offering opportunities for future research. MATERIALS AND METHODS This review is based on a literature study of scientific journals and books from libraries and electronic sources, such as ScienceDirect, PubMed and ACS. RESULTS As many as 65 compounds are included in this review. They belong to different classes of compounds including flavonoids, terpenoids and several other types of compounds, such as alkaloids, phenolic acids and amides. The pharmacological studies revealed that various types of preparations, extracts and single compounds of species from this genus exhibited a broad spectrum of biological activities including antioxidant, antimicrobial, anti-inflammatory and cytotoxic activities. However, Sapium glandulosum, Sapium indicum and Sapium sebiferum were reported to possess toxic effects and Sapium sebiferum was found to contain phorbol esters acting as a tumor-promoting agent. CONCLUSION The genus Sapium consists of 23 accepted (high confidence) species. However, only very few of species have been phytochemically and pharmacologically studied. There is great potential to discover new chemical constituents from this genus because only a few species have been phytochemically investigated thus far. Only 27 compounds of 65 identified compounds have been studied for their biological activities. Several extracts and single compounds from this genus were reported to exhibit interesting biological activities such as antimicrobial, antioxidant and cytotoxic effects. Furthermore, the toxicity studies of some phorbol esters suggested that the compounds acted as potential tumor-promoting agents by stimulating protein kinase C. This is an interesting fact in which a plant with medicinal properties also possesses toxic effects as well. Therefore, more clinical studies on the toxicity of the extracts of the plants and the compounds isolated from this genus are also crucial to ensure their safety and to assess their eligibility for use as sources for modern medicines.

Activity-Guided Isolation of Bioactive Constituents with Antinociceptive Activity from Muntingia calabura L. Leaves Using the Formalin Test

The present study was conducted to determine the antinociceptive potential of methanol extract of Muntingia calabura L. (MEMC) and to isolate and identify the bioactive compound(s) responsible for the observed antinociceptive activity. The MEMC and its partitions (petroleum ether (PEP), ethyl acetate (EAP), and aqueous (AQP) partitions), in the dose range of 100, 500, and 1000 mg/kg, were tested using the formalin-induced nociceptive test. The PEP, which exerted the most effective activity in the respective early and late phase, was further subjected to the fractionation procedures and yielded seven fractions (labelled A to G). These fractions were tested, at the dose of 300 mg/kg, together with distilled water or 10% DMSO (negative controls); morphine and aspirin (positive controls) for potential antinociceptive activity. Of all fractions, Fraction D showed the most significant antinociceptive activity, which is considered as equieffective to morphine or aspirin in the early or late phase, respectively. Further isolation and identification processes on fraction D led to the identification of three known and one new compounds, namely, 5-hydroxy-3,7,8-trimethoxyflavone (1), 3,7-dimethoxy-5-hydroyflavone (2), 2′,4′-dihydroxy-3′-methoxychalcone (3), and calaburone (4). At the dose of 50 mg/kg, compound 3 exhibited the highest percentage of antinociceptive activity in both phases of the formalin test. In conclusion, the antinociceptive activity of MEMC involved, partly, the synergistic activation of the flavonoid types of compounds.

Synthesis of novel disulfide and sulfone hybrid scaffolds as potent β-glucuronidase inhibitor.

Novel series of disulfide and sulfone hybrid analogs (1-20) were synthesized and characterized through EI-MS and (1)H NMR and evaluated for β-glucuronidase inhibitory potential. All synthesized analogs except 13 and 15 showed excellent β-glucuronidase inhibitory potential with IC50 value ranging in between 2.20-88.16μM as compared to standard d-saccharic acid 1,4 lactone (48.4±1.25μM). Analogs 19, 16, 4, 1, 17, 6, 10, 3, 18, 2, 11, 14 and 5 showed many fold potent activity against β-glucuronidase inhibitor. Structure activity relationship showed that substitution of electron withdrawing groups at ortho as well as para position on phenyl ring increase potency. Electron withdrawing groups at meta position on phenyl ring showed slightly low potency as compared to ortho and para position. The binding interactions were confirmed through molecular docking studies.