α-Mangostin was extracted from the pericarp of the Malaysian local Garcinia mangostana linn., The structure was characterised by Infrared red, UV-Visible and Nuclear Magnetic Resonance spectroscopic data. The fluorescence peak at 500nm in ethanol was not observed in PNIPAM microgel solution. The increase of colloidal size of the gel in the presence of α-mangostin was studied by Dynamic Light Scattering and Transmission Electron Microscope. The size of the particle also increases with increasing temperature up to 45⁰C after which it began to shrink. The TEM micrograph at 45°C showed a uniformly structured pattern of the gel occurs in the range of the lowest solution critical temperature.
Two adducts of bis(N-benzyl-N-isopropyldithiocarbamato) zinc(II) with 2,2'Â-bipyridine and 1,10-phenanthroline have been successfully synthesized and characterized by elemental analysis and spectroscopic studies. The IR specÂtra of these adducts showed the thioureide band, v(C---- N) which occurred at 1440 and 1438 cm-1 respectively, lower than the parent compound at 1471 cm-1. The 13C NMR spectroscopic data for these compounds showed that the carbon signal from CS2 moiety shifted slightly downfield to 206.6 and 208.5 ppm compared to the parent compound at 205.1 ppm. The single crystal structure of bis (N-benzyl-N-isopropyldithiocarbamato )zinc(II)(bipy) has been determined. The structure of this compound showed monomeric nature with hexacoordination of the metal in a highly distorted octahedral geometry.
Dua sebatian aduk zink(II) benzilisopropilditiokarbamat dengan ligan 2,2-bipiridil dan 1,10-fenantrolin telah berjaya disediakan dan dianalisis menggunakan analisis unsur dan kaedah spektroskopi. Spektrum IR untuk kedua-dua sebatian aduk ini telah menunjukkan kehadiran jalur tioureida, V(C----- N) pada 1440 dan 1438 cm-1 masing-masing yang mana jalur serapan ini didapati teranjak pada nilai yang lebih rendah berbanding sebatian asalnya iaitu pada 1471 cm-1. Data RMN 13C pula menunjukkan kehadiran signal karbon CS2 yang teranjak sedikit ke medan yang lebih rendah iaitu pada 206.6 dan 208.5 ppm masing-masing jika dibandingkan dengan sebatian asalnya pada 205.1 ppm. Struktur hablur tunggal bagi sebatian bis( N-benzilÂ-N-isopropilditiokarbamat)zink(11)(bipy) telah ditentukan. Struktur sebatian ini didapati bersifat monomerik dan berkoordinat enam dengan atom logam pusatnya mempunyai geometri oktahedron yang sangat terherot.
Andrographolide was separated from Andrographis paniculata Nees by using column chromatography and recrystallized from methanol. 1H and 13C NMR, IR, UV spectroscopic and GCMS data were in agreement with the previous report. The crystallined product has a monoclinic system with space group P21, a=6.541(1), b=8.003(1), c=17.962(2) Å and β=97.39(1)19o. The bicyclohexane fragments have a chair conformation with the methyl and the methylene hydroxyl groups occupying the axial position, while the OH and the C2-lactone are in the equatorial positions. The bond lengths and the angles are in the normal ranges. There are two intramolecular interactions of the type O-H … O and C-H …. O in the molecule. The molecule is stabilized by two interhydrogen bonds O-H … O and C-H … O to form polymeric chains parallel to b-axis.
Andrografolid telah dipisahkan daripada herba Andrographis paniculata Nees dengan kaedah kromatografi turus dan dihablur semula daripada metanol. Analisis spektroskopi RMN 1H dan 13C, 1M, UL, KGSJ bersetuju dengan laporan terdahulu. Hablur produk mempunyai sistem monoklinik dengan kumpulan ruang P21, a=6.541(1), b=8.003(1), c=I7.962(2)Å dan β =97.39(1)°. Fragmen bisikloheksana berkonformasi kerusi dengan kumpulan metil dan CH2OH mengisi kedudukan paksi. Kumpulan OH serta C2-lakton berada di kedudukan khatulistiwa. Panjang dan sudut ikatan adalah normal. Terdapat dua ikatan intrahidrogen O-H .... O dan satu C-H .. O. Molekul distabilkan oleh dua ikatan interhidrogen O-H ……O dan C-H .… O membentuk rangkaian polimer tak terhingga selari dengan paksi- b.
Chromatographic purification of chloroform extract of the twigs of Ellipeia cuneifolia has led to the discovery of three compounds comprising of 2´,4´-dihydroxy-4,6´-dimethoxychalcone; tepanone; and O-methylmoschatoline. Structures of the compounds were established by interpreting their spectral data and by comparing them with those of the literature. Two of them showed antibacterial activities.
Tujuan kajian ini adalah untuk mengkaji kebolehan hidrogel daripada selulosa bakteria (BC-g-PAA) sebagai pembawa bagi
menghasilkan nanozarah ferum oksida (FeNps). Hidrogel selulosa telah disintesis menggunakan kaedah pempolimeran
radikal bebas. Secara umum, kaedah pempolimeran radikal bebas ialah pempolimeran berantai (pempolimeran berion),
dengan monomer radikal bebas menyerang monomer lain yang ikatannya berganda sehingga membentuk rantai dan
akan melebarkannya. Nanozarah ferum oksida (FeNps) telah dihasilkan melalui gabungan antara 1 × 10-4 g/mL garam
ferosenium ke dalam sistem hidrogel, seterusnya agen penurun natrium oksida (NaOH) dengan kepekatan 1 M digunakan
untuk mendapatkan zarah. Hidrogel di dalam larutan penimbal pada pH10 ialah yang mempunyai nisbah pembengkakan
tertinggi. Keputusan FTIR menunjukkan bahawa asid akrilik (AA) berjaya dicangkukkan pada jaringan selulosa bakteria
(SB). Imej hidrogel telah dicirikan melalui analisis mikroskopi elektron imbasan (SEM), diikuti oleh spektroskopi tenaga
serakan X-ray (SEM-EDX) dalam penentuan peratusan elemen ferum (Fe). Nanozarah berhasil diperolah selepas hidrogel
dikalsinkan, seterusnya zarah tersebut diuji melalui mikroskopi transmisi elektron (TEM) dan pembelauan sinar-X
(XRD). Analisis TEM menunjukkan diameter zarah berukuran 5 - 20 nm. Keputusan XRD mengesahkan bahawa zarah
yang diperoleh ialah ferum oksida (Fe3
O4
) yang terletak pada puncak 2θ; 32°, 35°, 49° and 54°. Semua keputusan yang
diperoleh menunjukkan bahawa hidrogel berasaskan selulosa bakteria berjaya digunakan sebagai nanoreaktor untuk
menghasilkan nano zarah ferum oksida (FeNps)
C-4-phenacyloxy phenyl calix[4]resorcinarene (CPPCR) was synthesized by acidic condensation of 4-hydroxybenzaldehyde
and resorcinol. The adsorption of CPPCR for Pb(II), Cd(II) and Cr(III) has been studied by measuring the metal
concentration in aqueous solution using Atomic Absorption Spectrophotometry (AAS). The effects of solution pH, contact
time and initial concentration of metal ions on the adsorption capacity of CPPCR were investigated. The adsorption kinetic
of all the ions obeyed the Ho and McKay pseudo 2nd order rate law and the adsorption isotherm profile matched very well
with Langmuir model. The separation factor (RL
) of CPPCR for Pb(II), Cd(II) and Cr(III) were 0.190, 0.017, and 0.065,
respectively, indicating the formation of monolayer behaviour. The Gibb free energy (ΔG) of the adsorption for all the
metal ions have negative values indicating the adsorption process of Pb(II), Cd(II) and Cr(III) by CPPCR are spontaneous.