Abdul Hamid

Lapidilectine A and lapidilectine B, two new alkaloids from Kopsia lapidilecta

Abstract Bark and leaves of Kopsia lapidilecta Van der Sleesen were extracted. Two new indole alkaloids were afforded: lapidilectine A 1 (bark) and lapidilectine B 2 (leaves). Both possess a novel skeleton with a five membered unsaturated ring. The structures of these alkaloids were elucidated especially by 2D NMR analysis.

A PRELIMINARY CHEMOTAXONOMIC REVIEW OF KOPSIA (APOCYNACEAE)

The present paper is the result of a botanical and chemical study of the Indo-Pacific genus Kopsia (Plumerioideae-Rauvolfieae) Apocynaceae. Some of the species of this genus possess medicinal uses. A survey of the accepted taxa and their synonymy, based on the study of types, is presented. Studies on alkaloids provides chemotaxonomic information. Indeed, in some cases, chemical relationships occur between species belonging to the same botanical group.

Monomargine, a nitrogenous cytotoxic pigment from Monocarpia marginalis

Abstract Monomargine 1 , a new nitrogenous pigment, was isolated from the bark of Monocarpia marginalis and its structure elucidated by 2D NMR analysis. 1 exibited cytotoxic activity in vitro against the growth of KB and P388 cells (IC 50 0.7 μ/ml).

Secotirucallane triterpenes from the stem bark of Aglaia leucophylla

Abstract Bioactivity guided fractionation of an ethanolic extract of the stem bark of Aglaia leucophylla led to the isolation of two new 3,4-secotirucallane type triterpenoids, namely (24 Z )-3,4-secotirucalla-4(28),7,24-triene-3,26-dioic acid and its 3-monomethyl ester, together with five known triterpenoids [(+)-ocotillone, (+)-ocotillol, (+)-cabraleone, (+)-cabralealactone and (+)-eichlerianic acid] and one known sesquiterpene [(−)-caryophyllene oxide].

A new sesquiterpenoid from the rhizomes of Homalomena sagittifolia

A new sesquiterpenoid, 1α,4β,7β-eudesmanetriol (1), was isolated together with the known compounds 1β,4β,7β-eudesmanetriol (2) and oplopanone (3) from the rhizomes of Homalomena sagittifolia. The structures of these compounds were determined by extensive spectral analyses. The compounds 1 and 2 inhibited growth of Pseudomonas stutzeri with a MIC value of 117 µM when evaluated for antibacterial activity using the minimum concentration assay. Both these compounds showed remarkable activities against acetylcholinesterase enzyme with IC50 values ranging between 25 and 26 µM. The isolation of these sesquiterpenoids and their biological activities observed in this study support the reported traditional uses of H. sagittifolia for the treatment of microbial related diseases and central nervous system disorders.

catena-Poly[[sodium-di-μ-β-d-glucose] chloride]

The asymmetric unit of the title compound, {[Na(C6H12O6)2]Cl}n, contains six glucose molecules, three Na+ ions and three Cl− ions, i.e. three independent {[Na(C6H12O6)2]Cl} units. Each of these units forms polymeric chains along the c axis. Each Na+ ion is surrounded by six O atoms from four glucose molecules, forming a distorted octahedral geometry. All glucose molecules adopt chair conformations. The constituent units are linked into a three-dimensional framework by O—H⋯Cl and O—H⋯O hydrogen bonds, utilizing all the O—H groups.

Monocarpin, a new cycloartane from Monocarpia marginalis

Abstract Monocarpin 1, a new cycloartane derivative, was isolated from the trunk bark of Monocarpia marginalis J. Sinclair and its structure elucidated primarily by 2D NMR.

Kinetic Modelling for Hydrogen Reduction of Ferric Oxide Using MATLAB

Research on reduction of ferric oxide is most important studied topics due to importance of iron and steel in the current and future technologies. In this research, a kinetic model for hydrogen reduction of ferric oxide has been developed by using the MATLAB software. This model can be used to determine the transport-limited reaction rate for reduction of ferric oxide in hydrogen atmosphere. The reduction is predicted from independently measured physical and thermodynamic properties of the reaction system and experimentally measured properties of the reactant solid (Fe2O3), gas phase (H2 gas) and resulting reaction product (Fe). In this research, experimentally observed reaction rate is significantly slower than the predicted transport-limited rate. There is a gap occurs between the predicted and experimental results although the model explicated the trend and the behaviour of reduction rate of ferric oxide and indicated a good homogeneity to the experimental conditions used in this research.

FRAGMENTATION AND CONFLICT AMONG ISLAMIC POLITICAL PARTIES IN INDONESIA DURING REFORMASI ERA (1998-2009): Anatomy, Factors and Implications

Since independence of the Republic of Indonesia, Muslims, as the majority population, have established diverse Islamic political parties. The nature of such parties has changed from the days of the Old Order to the New Order and Reformasi eras. Despite similar anatomies between Islamic parties of the Old Order and those of Reformasi, Islamic political parties profess different ideological missions. While the beginning of Old Order saw the confederation of Islamic political parties, Masyumi, seeking to promote the establishment of an Islamic State, none of the Islamic political parties which mushroomed during Reformasi era expressly struggled for the establishment of an Islamic state. However, the Islamic political parties had to weather similar problems of internal conflict and fragmentation. Different ideological strands, policy stances and leadership styles are believed to be amongst the pivotal root causes of their domestic troubles. With their popular votes and parliamentary seats significantly reduced, they prove to be no competition to the nationalist political parties.