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Kemunculan strain parasit yang rintang terhadap hampir semua ubatan antimalaria telah mendorong para saintis mengkaji penggantian mekanisme tindakan alternatif yang lebih berkesan. Keberkesanan rawatan semasa antimalaria adalah terhad dari segi bio ketersediaan ubat yang rendah, ketoksikan ubat yang tinggi dan kadar keterlarutan dalam air yang rendah. Penghibridan adalah satu strategi menarik bagi mengembangkan konsep penemuan ubat antimalaria. Kerangka 4-aminokuinolina telah disasarkan dalam kebanyakan proses reka bentuk agen antiplasmodium kerana kos sintesisnya yang murah, selamat dan kurang toksik sejak 20 tahun yang lalu. Penemuan hibrid antiplasmodium menggunakan kerangka 4-aminokuinolina dan pelbagai moieti seperti artemisinin, piperidin, indolin, pirimidin telah menunjukkan aktiviti antiplasmodium yang baik. Walau bagaimanapun, sehingga kini penemuan hibrid ini masih tidak dapat dibangunkan dan memasuki ujian percubaan klinikal. Ulasan ini meringkaskan penemuan hibrid antiplasmodium yang telah diterbitkan dalam tempoh sebelas tahun ke belakang (2011-2021). Kelebihan dan kelemahan konsep penghibridan sebagai pengganti agen antiplasmodium sedia ada dibincangkan. Analisis kajian menunjukkan hibrid 4-aminokuinolina mempunyai aktiviti antiplasmodium yang setanding atau lebih baik secara in vitro berbanding rawatan profilaksis klorokuina. Hibrid kuinolina kelas IV adalah yang paling kerap dikaji dan diperoleh dalam kajian ini sepanjang tempoh sebelas tahun ke belakang. Kekurangan data praklinikal terperinci mengenai hibrid yang disintesis telah menghalang kajian lanjut dalam ujian klinikal.

Malaria masih lagi kekal menjadi salah satu penyakit endemik yang boleh membawa maut dan rawatan yang digunakan kini untuk merawat malaria adalah terapi gabungan artemisinin. Namun begitu, akses kepada rawatan ini adalah sangat terhad dan memberi kesan besar kepada negara miskin disebabkan kos terapi yang tinggi. Penilaian aktiviti antimalaria bagi kompleks organologam berasaskan ligan makroksiklik tetraaza masih kurang meluas dijalankan. Ligan makrosiklik tetraaza 5,5,7,12,12,14- heksametil-1,4,8,11- tetraazasiklotetradeka-7,14-dienium bromida, dikomplekskan dengan empat logam peralihan iaitu Cu(II), Pb(II) dan Ni(II) dan Cd(II). Aktiviti antimalarial secara in vitro ke atas strain parasit Plasmodium falciparum yang rintang terhadap klorokuina, K1 ditentukan dan dibandingkan dengan aktiviti antiplasmodial sebatian klorokuina dan artemisinin. Kompleks [Cd(L)(OAc)]Br- merencat pertumbuhan parasit dengan 50% kepekatan perencatan berkesan (EC50) dalam julat aktiviti antiplasmodium yang poten (EC50100 μM). Nilai indeks pemilihan yang tinggi turut ditunjukkan oleh kompleks Cd(II) iaitu 60.5 seterusnya menjadikan kompleks ini berpotensi untuk dibangunkan sebagai agen antimalaria.

Jangkitan malaria adalah penyakit berjangkit serius yang disebabkan oleh parasit plasmodium dan harus dirawat sebagai perubatan kecemasan. Sehingga kini, tiada vaksin yang sudah dikomersialkan untuk mencegah malaria. Enam sebatian porfirin logam nikel(II) dan zink(II) berasaskan porfirinmeso bebas bes 5,15-difenilporfirin (2), 5,15-diheksilporfirin (3) dan 5,10,15,20-tetrafenilporfirin (4) iaitu NiDDHP, NiDPP, NiTPP, ZnDHP, ZnDPP dan ZnTPP dihasilkan melalui penyejatan Lindsey sebelum dicirikan secara spektroskopi (resonans magnet nukleus, ultra lembayung boleh nampak, spektrometri jisim) dan fizikal (takat lebur). Aktiviti antiplasmodium dan kesitotoksikan secarain vitro terhadap strain rintang-klorokuina, P. falciparum K1 dinilai dan dibandingkan dengan aktiviti antiplasmodium dadah rujukan seperti klorokuina dan artemisinin. ZnDHP, ZnTPP dan NiDPP merencat pertumbuhan parasit dengan 50% kepekatan perencatan berkesan (EC50) dalam julat aktiviti antiplasmodium sederhana iaitu 21.4 sehingga 36.0 µM. Aktiviti kesitotoksikan terhadap sel mamalia Vero yang ditunjukkan oleh NiDPP, ZnDHP dan ZnTPP berada dalam julat tidak toksik iaitu 97 sehingga 587 µM. ZnDHP mempunyai nilai indeks pemilihan yang paling tinggi iaitu 27.2 µM, menunjukkan aktiviti antiplasmodium yang selektif terhadap perencatan plasmodium dan tidak toksik terhadap sel mamalia.

Malaria poses a severe public health risk and a significant economic burden in disease-endemic countries. One of the most severe issues in malaria control is the development of drug resistance in malaria parasites. The standard treatment for malaria is artemisinin-combination therapy (ACT). Nevertheless, the Plasmodium parasite's extensive resistance to prior drugs and reduced ACT efficiency necessitates novel drug discovery. The progress in discovering novel, affordable, and effective antimalarial agents is significant in combating drug resistance, and the hybrid drug concept can be used to covalently link two or more active pharmacophores that may act on multiple targets. Pyrazole and pyrazoline derivatives are considered pharmacologically necessary active heterocyclic scaffolds that possess almost all types of pharmacological activities. This review summarized recent progress in antimalarial activities of synthesized pyrazole and pyrazoline derivatives. The studies published since 2000 are included in this systematic review. This review is anticipated to be beneficial for future study and new ideas in searching for rational development strategies for more effective pyrazole and pyrazoline derivatives as antimalarial drugs.

Background: Sufficient intake of macronutrients and micronutrients are essential for child growth. Many children with autism spectrum disorder (ASD) however are reported to be picky eaters which may lead to malnourishment. As diet and behaviour are importantly interconnected, this study aims to determine the level of knowledge on nutrition among parents and special educators of children with ASD. Methods: A cross-sectional study was conducted at a National Autism Centre in Kuala Lumpur, Malaysia from May to August 2018. A 37-item questionnaire was self-administered to the respondents who attended a series of training of trainers’ sessions. The data was collected and analysed descriptively. A total of 209 respondents participated with 153 parents and 56 special educators of children with ASD. Results: Only 37.9% of the parents agreed that their children’s diet contains balanced nutrition. Majority of the parents and special educators had the perception that sugar, junk food and gluten are bad for the children, but they were still given due to the accessibility and convenience. Conclusion: The low level of knowledge among parents and special educators about the nutrition of children with ASD indicates that a measure should be taken to increase awareness and to overcome the malnutrition among ASD children. Keywords: gluten, casein, diet, supplement, malnutrition DOI : http://dx.doi.org/10.17576/JSKM-2021-1901-14

Aminoalkylated chalcone compounds (4a-4c) have been designed using Quantitative Structure-Activity Relationship (QSAR) analysis, synthesized and evaluated for their in vitro antimalarial activity. The best QSAR model obtained was log IC50 = 705.132 (qC7) - 65.573 (qC3) - 24.845 (qC4) - 4.634 (qC13) - 220.479 and statistical analysis showed R2 of 0.937, suggesting that the QSAR model was able to predict the actual antimalarial activity by 93.7% accuracy. The addition of secondary amines to the chalcone compounds was successfully carried out using the Mannich reaction, which was confirmed by spectroscopic analysis. The in vitro antimalarial activity of the synthesized compounds were screened against the 3D7 strain of Plasmodium falciparum (CQ sensitive). All of the compounds exhibited strong activity with IC50 values ranging from 0.54 ± 0.649 to 1.12 ± 0.369 µM. The molecular docking studies investigated interactions of the prepared compounds to the binding site of wild-type Plasmodium falciparum dihydrofolate reductasethymidylate synthase (Pf-DHFR-TS) (PDB ID: IJ3I) and quadruple mutant Pf-DHFR-TS (PDB ID: IJ3K). Some hydrogen bond and π – π interactions were observed with the side chain of Ala16, Asp54, Cys15, Leu164, Tyr170, and Met55 in both the wild and mutant Pf-DHFR types. It has also been found that all the tested compounds were obeyed the Lipinski’s rule. This study proposed that compound 4b can be developed as the new lead of the antimalarial agent.

Malaria is a potentially deadly disease with many anti-malarial drugs have been rendered ineffective due to Plasmodium falciparum resistance concern. Plasmodium falciparum lactate dehydrogenase (PfLDH) enzyme is a crucial malaria parasite enzyme involved in the glycolytic pathway, thus, has been considered as a potential molecular target. Initially, molecular docking was performed using AutoDock Vina, Molegro Virtual Docker, and CDOCKER software to investigate the molecular interactions of 4-aminoquinoline antimalarial hybrids compounds with PfLDH enzyme. All ten 4-aminoquinoline hybrids derivatives docked to the PfLDH binding site. The results showed that these compounds exhibited either comparable or higher binding affinity than the reference drug chloroquine, amodiaquine, and hydroxychloroquine. Visually, some of the compounds possessed functional binding interactions, possibly due to their similar structural conformation and binding interactions of chloroquine in the binding site. Apart from that, the docking results also suggest that these compounds potentially promote additional hydrogen-bonding interactions with the residues in the binding site. Interestingly, the compounds also predicted to interact with essential PHE52, VAL26, ILE54, ILE119, and ALA98 residues, which are required to act as a competitive inhibitor for this glycolytic enzyme.

Early bacterial infection (BI) identification in resource-limiting Emergency Departments (ED) is challenging, especially in low- and middle-income counties (LMIC). Misdiagnosis predisposes to antibiotic overuse and propagates antimicrobial resistance. This study evaluates new emerging biomarkers, secretory phospholipase A2 group IIA (sPLA2-IIA) and compares with other biomarkers on their performance characteristic of BI detection in Malaysia, an LMIC. A prospective cohort study was conducted involving 151 consecutive patients admitted to the ED. A single measurement was taken upon patient arrival in ED and was analysed for serum levels of sPLA2-IIA, high-sensitive C-reactive protein (CRP), procalcitonin (PCT), neutrophil percentage (N%), and lactate. All biomarkers’ performance was compared for the outcomes using area under the receiver operating characteristic curve (AUROC), sensitivity, and specificity. The performance of sPLA2-IIA (AUROC 0.93 [95% CI: 0.89–0.97]; Sn 80% [95% CI: 72–87]; Sp 94% [95% CI: 81–89]) was the highest among all. It was comparable with high-sensitive CRP (AUROC 0.93 [95% CI: 0.88–0.97]; Sn 75% [95% CI: 66–83]; Sp 91 [95% CI: 77–98]) but had a higher Sn and Sp. The sPLA2-IIA was also found superior to N%, PCT, and lactate. This finding suggested sPLA2-IIA was recommended biomarkers for BI detection in LMIC.

Neuropathic pain is a chronic pain condition persisting past the presence of any noxious stimulus or inflammation. Zerumbone, of the Zingiber zerumbet ginger plant, has exhibited anti-allodynic and antihyperalgesic effects in a neuropathic pain animal model, amongst other pharmacological properties. This study was conducted to further elucidate the mechanisms underlying zerumbone’s antineuropathic actions. Research on therapeutic agents involving cannabinoid (CB) and peroxisome proliferator-activated receptors (PPARs) is rising. These receptor systems have shown importance in causing a synergistic effect in suppressing nociceptive processing. Behavioural responses were assessed using the von Frey filament test (mechanical allodynia) and Hargreaves plantar test (thermal hyperalgesia), in chronic constriction injury (CCI) neuropathic pain mice. Antagonists SR141716 (CB1 receptor), SR144528 (CB2 receptor), GW6471 (PPARα receptor) and GW9662 (PPARγ receptor) were pre-administered before the zerumbone treatment. Our findings indicated the involvement of CB1, PPARα and PPARγ in zerumbone’s action against mechanical allodynia, whereas only CB1 and PPARα were involved against thermal hyperalgesia. Molecular docking studies also suggest that zerumbone has a comparable and favourable binding affinity against the respective agonist on the CB and PPAR receptors studied. This finding will contribute to advance our knowledge on zerumbone and its significance in treating neuropathic pain.

The sensitive and rapid detection of hydrogen peroxide is very important in the areas of clinical and environmental analyses. A sensitive and selective Horseradish peroxidase (HRP)-hydrogen peroxide (H2O2) biosensor was developed based on acrylic microspheres. Hydrophobic poly(n-butyl acrylate-N-acryloxysuccinimide) [poly(nBA-NAS)] microspheres were synthesized using photopolymerization in an emulsion to form an enzyme immobilization matrix. The HRP enzyme was covalently immobilized onto the acrylic microspheres via the succinimide functionality. Field emission scanning electron microscope (FESEM) has been utilized to characterize the screen-printed carbon paste electrode (SPE) constructed from enzyme conjugated acrylic microspheres and gold nanoparticles (AuNPs) composite (HRP/nBA-NAS/AuNPs/SPE). Differential pulse voltammetry was used to assess the biosensor performance. The linear response range of the hydrogen peroxide biosensor obtained was from 1.0 × 10-2 to 1.0 × 10-10 M (R2 = 0.99) with the limit of detection (LOD) approximately at 1.0 × 10-10 M. This is an improvement over many hydrogen peroxide biosensors reported so far. Such improvement may be attributed to the large surface area provided by the acrylic microspheres as a matrix for immobilization of the HRP enzyme.

A copper ion sensor based on a new bis-thiourea compound N1,N3-bis[[3,5-bis(trifluoromethyl)phenyl]carbamothioyl]isophthalamide (or TPC) as neutral carrier was investigated. The immobilization of the TPC into poly(n-butyl acrylate) (pBA) membrane via drop casting and the sensor was characterized by potentiometry. The sensor fabricated from TPC only showed a good Nernstian response towards copper ion with a sensitivity slope of 28.81±0.53mV/decade in the range of 1.0 × 10-6 - 1.0 × 10-4 M. The limit of detection of this sensor was found to be 6.11 × 10-7 M and with short sensor response time (60 - 80 s). This sensor also demonstrated reversibility and reproducibility with 3.69% and 1.84% (Relative Standard Deviation, RSD), respectively. Based on the separate solution method (SSM), the logarithm selectivity coefficients were better than -2.00 for monovalent, divalent and trivalent cations and this confirmed that the sensor exhibited good selectivity towards copper ion. The sensor could attain optimum function without the need in the inclusion of either lipophilic anions as a membrane additive nor plasticizer as a membrane softener. Thus, these are the main advantages. The addition of lipophilic anions into the pBA membrane could cause the sensitivity and selectivity of the copper ion sensor based on ionophore TPC to deteriorate.

Early bacterial infection (BI) identification in resource-limiting Emergency Departments (ED) is challenging especially in low- and middle-income counties (LMIC). Misdiagnosis predisposes to antibiotic overuse and propagates antimicrobial resistance. This study evaluates new emerging biomarkers, secretory phospholipase A2 group IIA (sPLA2-IIA), and compares with other biomarkers on their performance characteristic of BI detection in Malaysia, an LMIC. A prospective cohort study was conducted involving 151 consecutive patients admitted to the ED. A single measurement was taken upon patient arrival in ED and was analysed for serum levels of sPLA2-IIA, high-sensitive C-reactive protein (CRP), procalcitonin (PCT), neutrophil percentage (N%), and lactate. All biomarkers’ performance was compared for the outcomes using area under the receiver operating characteristic curve (AUROC), sensitivity, and specificity. The performance of sPLA2-IIA (AUROC 0.93 [95% CI: 0.89-0.97]; Sn 80% [95% CI: 72-87] Sp 94% [95% CI: 81-89]) was the highest among all. It was comparable with high-sensitive CRP (AUROC 0.93 [95% CI: 0.88-0.97]; Sn 75% [95% CI: 66-83]; Sp 91 [95% CI: 77-98]) but had a higher Sn and Sp. The sPLA2-IIA was also found superior to N%, PCT, and lactate. This finding suggested sPLA2-IIA was recommended biomarkers for BI detection in LMIC.

Abundant of preparatory works have recognized that fluorescent sensors based on 8-aminoquinoline are popular tools to detect Zn2+ ions in environmental and biological applications. Along with these studies, researchers started to introduce a variety of carboxamido group into an 8-aminoquinoline molecule in forming 8-amidoquinoline derivatives. Therefore, this systematic review aims to introduce a general overview of the fluorophore 8-aminoquinoline as Zn2+ receptors and to provide comparisons of collected studies that related to 8-amidoquinoline derivatives as fluorophore probe of the sensor. According to PRISMA systematic searches strategy, 13 articles were analyzed for trends, research designs, results and discussion, subject samples, and remarks or conclusions. We found cross-sectional studies with four aspects in zinc sensing that have been targeted; binding studies via titration, detection's limit, interferences studies, and validation of the study. Hence, this paper also included assessments of those criteria and the trends of development of 8-amidoquinoline derivatives based-zinc fluorescent chemosensor. It also showed that most of the researches conducted in China. In conclusion, this study identified various research designs of fluorescent chemosensors based on 8-amidoquinoline prolong with the effectiveness and potential as a recognition probe to assist the detection of zinc. Hence, elucidation of those derivatives essential to be explored because more studies are needed to improve the sensing criteria of the zinc sensor

Inhibition of acetylcholinesterase (AChE) enzyme is a known procedure to treat severe Alzheimer's disease through increasing the acetylcholine level in the brain and thus slowing down the progression of Alzheimer's symptoms. The approved medications are only considered as palliative and addressed some reported deficiencies. Therefore, the demand for safe and effective compounds is substantially increasing. A newly series of coumaryl 1,3-selenazoles derivatives was synthesized in four steps. Then, their antioxidant activities were evaluated using DPPH, ABTS cation radical scavenging assay and cupric reducing antioxidant capacities (CUPRAC). The anticholinesterase activities were evaluated using the Ellman method. Then, the docking studies were carried out to explain the possible correlation between in vitro anticholinesterase activity results and the ligand-receptor interactions. Ten new coumaryl 1,3-selenazoles (5a-5d series and 6a-6f series) derivatives were successfully synthesized. The DPPH radical scavenging assay showed that all tested compounds have IC50 value > 200 μM, for ABTS cation radical scavenging assay the IC50 value > 1000 μM and for CUPRAC assay the IC50 value > 200 μM. Compound 5c was found to be the most active compound against AChE and BChE in its series with IC50 value for AChE is 99.76 μM and IC50 for BChE is 140.28 μM while 6b exhibited the most potent inhibition in its series with IC50 value for AChE is 56.01 μM and IC50 for BChE is 121.34 μM. Besides, the docking studies showed that compound 5c and 6b formed π-π stacking interaction with aromatic residues at the active site of AChE and BChE, which is responsible for inhibiting the enzymes. This shows that the synthesized compounds contain skeletal structures that can interact and inhibit within the enzymes active site.

Borylated porphyrin is one of building blocks in coupling reactions to obtain the multiporphyrin containing two, three or more subunits of porphyrins. In this study, one of borylated porphyrin derivatives, 5-(4,4,5,5 – tetramethyl – 1,3,2 – dioxoborolane) -10,20 – diphenylporphyrin (B-DPP) was synthesized through four steps of reactions. The building block of porphyrin, dipyrromethane was synthesized through a condensation reaction in the presence of trifluoroacetic acid as catalyst. Subsequently, A2B2 type of porphyrin was obtained by Lindsey condensation reaction followed by bromination reaction to produce porphyrin halide. Suzuki cross coupling reaction between porphyrin halide and pinacolborane with Pd (II) catalyst afforded 40% of borylayed porphyrin. The product was successfully characterized by using nuclear magnetic resonance spectroscopy (NMR) and UV-Visible spectroscopy (UV-Vis). This compound crystallized from a mixture of dichloromethane/methanol to give violet needle-like crystal. Crystallographic studies showed this compound crystallized in monoclinic system with space group of P21/c.

A toxicity electrochemical DNA biosensor has been constructed for the detection of carcinogens using 24 base guanine DNA rich single stranded DNA, and methylene blue (MB) as the electroactive indicator. This amine terminated ssDNA was immobilized onto silica nanospheres and deposited on gold nanoparticle modified carbon-paste screen printed electrodes (SPEs). The modified SPE was initially exposed to a carcinogen, followed by immersion in methylene blue for an optimized duration. The biosensor response was measured using differential pulse voltammetry. The performance of the biosensor was identified on several anti-cancer compounds. The toxicity DNA biosensor demonstrated a linear response range to the cadmium chloride from 0.0005 ppm to 0.01 ppm (R2 = 0.928) with a limit of detection at 0.0004 ppm. The biosensor also exhibited its versatility to screen the carcinogenicity of potential anti-cancer compounds.

An efficient and a green route to synthesize phthalide-fused indoline, 3-[(5-chloro-1,3,3-trimethylindolin-2-ylidene)methyl] isobenzofuran-1(3H)-one (3) has been developed by the coupling reaction of 5-chloro-2-methylene-1,3,3-trimethylindoline, 1 and 2-formylbenzoic acid, 2 under solvent-free domestic microwave irradiation. The compound was produced in 85% yield. Compound 3 was characterized by analytical and spectral methods and its structure was confirmed by chemical crystallography. Compound 3 was successfully crystallized in triclinic system with space group Pī. The molecular structure consists of fused 1 and 2 groups connected by the enamine carbon. Binding study of 3 towards different types of metal cations was done by colorimetric detection and UV-vis titrations. Compound 3 exhibited good selectivity and sensitivity for Sn2+ compared to other metal cations tested. The stoichiometric binding ratio of 3 toward Sn2+ is found to be 1:1 and the binding constant (Ka) is 1.07×104 M–1 on the basis of Job’s plot and Benesi-Hildebrand analysis.

Chemistry is a branch of science pioneered by Muslim scholars. However, secularism has separated science from Islamic teachings, thus deviating man from Allah. Tauhidic Science Seminar was held to disseminate knowledge and findings between researchers from science background and Islamic study to students and lecturers in the Faculty of Science and Technology, Universiti Kebangsaan Malaysia. Questionaires were distributed to the participants after the seminar to obtain their understanding and perception of integrating science and Islam. Results indicate that 93.8% from 65 respondents have high affinity to science but only 63.1% were exposed to integration of science and Islam. Furthermore, 63.1% respondents understand the meaning of secularism and 69.2% realized that chemical elements have been mentioned in the Holy Quran. This study also indicates more than 90% respondents agree science and Islam are linked in an integrated manner. In conclusion, integration of science and Islam or Tauhidic Science drives us to explore and learn about nature through science activities based on Islam with guidance by the Holy Quran and hadith. Therefore, more proactive and holistic efforts need to be done to educate and strengthen the understanding of Tauhidic Science to students as early as in primary schools. Abstrak Kimia merupakan salah satu cabang ilmu sains yang telah lama dipelopori oleh ilmuwan Islam. Walau bagaimanapun, sekularisme telah menjadikan sains terpinggir dari Islam, apatah lagi merapatkan hubungan di antara manusia dan Pencipta. Seminar Sains Tauhidik telah diadakan untuk menghebahkan pengetahuan dan penemuan oleh penyelidik dari latar belakang sains dan pengajian Islam kepada pelajar dan pensyarah di Fakulti Sains dan Teknologi, Universiti Kebangsaan Malaysia. Borang soal selidik tentang pemahaman dan persepsi berkenaan penyepaduan sains dan Islam telah diagihkan kepada peserta selepas tamat seminar. Hasil kajian mendapati 93.8% responden meminati sains tetapi hanya 63.1% pernah didedahkan kepada pembelajaran berintegrasi sains dan Islam. Selain itu, 63.1% memahami maksud sekularisme dan 69.2% menyedari unsur kimia ada disebut di dalam al-Quran. Kajian ini juga menunjukkan bahawa lebih 90% responden bersetuju sains dan Islam dikaitkan dengan cara bersepadu. Kesimpulannya, integrasi sains dan Islam atau Sains Tauhidik memandu kita meneroka dan mempelajari tentang alam ini melalui aktiviti sains berlandaskan Islam berpandukan al-Quran dan hadis. Oleh itu, usaha-usaha yang lebih proaktif dan holistik perlu dilakukan untuk mendidik dan mengukuhkan kefahaman Sains Tauhidik kepada pelajar seawal di sekolah rendah lagi.

A unique, non-leaching and durable novel anti-biocide polyacrylamide-starch coating (pAam-g-S) has successfully been synthesized. In this study, a grafted cationic-functionalized polymeric coating was designed and cross-linked with native starch extracted from Dioscorea hispida sp. yam to afford multifunctional anti-fungal and anti-termite coating. Leaching of the disinfectant into the environment was eliminated because no toxic chemicals were used. The copolymerization was successfully carried out to produce various ratios of pAam-g-S coating using modification of starch-gel. Results obtained from Fourier Transform Infrared-Attenuated Total Reflectance (FTIR-ATR) confirmed the monomer pAam was grafted onto the starch backbone as shown by the cross-linked peak at 1642 cm−1. Supported by differential scanning calorimetry (DSC), the highest transition glass temperature was observed at 154 °C. The coating was designed to continuously decontaminate against pathogenic fungus and termite in addition to afford preliminary anti-biocides properties. Facile anti-fungal and anti-termite evaluations were conducted via total weight loss of wood (%) studies using white rot fungus, Pycnoporus. sanguineus and termite Coptotermes curvignathus respectively. In order to verify the coating performance, gel fractions, morphologies and heat resistant properties were also investigated.

Mass-spectrometry-based and X-ray fluorescence-based techniques have allowed the study of the distribution of Zn2+ ions at extracellular and intracellular levels over the past few years. However, there are some issues during purification steps, sample preparation, suitability for quantification, and the instruments’ availability. Therefore, work on fluorescent sensors based on 8-aminoquinoline as tools to detect Zn2+ ions in environmental and biological applications has been popular. Introducing various carboxamide groups into an 8-aminoquinoline molecule to create 8-amidoquinoline derivatives to improve water solubility and cell membrane permeability is also a recent trend. This review aims to present a general overview of the fluorophore 8-aminoquinoline and its derivatives as Zn2+ receptors for zinc sensor probes. Various fluorescent chemosensor designs based on 8-amidoquinoline and their effectiveness and potential as a recognition probe for zinc analysis were discussed. Based on this review, it can be concluded that derivatives of 8-amidoquinoline have vast potential as functional receptors for zinc ions primarily because of their fast reactivity, good selectivity, and bio-compatibility, especially for biological applications. To better understand the Zn2+ ion fluorophores’ function, diversity of the coordination complex and geometries need further studies. This review provides information in elucidating, designing, and exploring new 8-amidoquinoline derivatives for future studies for the improvement of chemosensors that are selective and sensitive to Zn2+.

The antimicrobial activities of eleven maleimide derivatives were tested in this study. Out of the eleven samples, N-(4fluorophenyl) maleimide, N-(4-chlorophenyl) maleimide and N-(4-bromophenyl) maleimide were synthesized by reacting maleic anhydride with 4-fluorophenylaniline, 4-chlorophenylaniline and 4-bromophenylaniline, respectively in the presence of acetic acid, by refluxing overnight. Crystals were successfully obtained after the products were recrystallized with different mixture of solvents. Their chemical structures were confirmed by infrared spectroscopy (IR), H and C Nuclear Magnetic Resonance (NMR) and melting point determination. Subsequently, all the samples were screened for their biological activity using disc diffusion method. The bacteria chosen for this study were Gram-negative Escherichia coli, Gram-positive Bacillus subtilis and yeast Saccharomyces cerevisae. Positive control for bacteria was streptomycin and nystatin for the yeast. M1 to M6 compounds gave remarkable result at low concentrations whereas M8, M9 and M11 compounds are mostly inactive up to a high concentration. In contrast, the unsubstituted maleimide, M7 was highly reactive towards both bacteria and yeast at low and high concentrations.

Thioureas play an important role in medicinal chemistry and agricultures due to their biological activity such as antibacterial, antifungal, antiviral, herbicides, rodenticides, phenoloxidase enzymatic inhibitors, anti-HIV and anti-tumor agents. In this study, five substituted bis-thioureas have been synthesized. The isophataloyl chloride and 2,6pyridinedicarbonyl dichloride were easily converted to bis-isothiocyanate compound via the reaction with ammonium thiocyanate by solid–liquid phase transfer catalysis of polyethylene glycol-400 (PEG-400). Bis-isothiocyanate compound was reacted with aniline derivatives to produce substituted bis-thioureas in good yield at room temperature. All the novel compounds were obtained as yellow solid after recrystallization using DMF/EtOH/H2O. Their c h e m i c a l structures were confirmed by Infrared spectrosopy (IR), Nuclear Magnetic Resonance (NMR) H and C and mass spectrometry. The five synthesized compounds were screened for antimicrobial activities using disc diffusion method for antimicrobial activity against Gram-positive bacteria (Bacillus Subtilis and Staphylococcus Aureus), Gram-negative bacteria (Escherichia Coli and Salmonella Typhi) and a mold (Aspergillus Niger). All tested compounds showed low antimicrobial activity since the diameter of inhibition zone (IZ) measure was less than positive control inhibition zone.

Being abundant in many tropical part of the world, Dioscorea sp. as food is limited due to its toxicity. However polysaccharides derive from these tubers could be important for other applications. Here we developed a Highly Luminescent Carbon Nanodots (C-dots) via acid hydrolysis of Gadong starch (GS). The hydrolysis rate of GS increased from 49% to 86% within 7 days while the X-ray diffraction showed the native GS particle is a C-crystalline type. The GS particles were either round or oval with diameters ranging from 50-90 nm. Further acid dehydration and surface oxidation reduced the size of GS nanoparticles to 6-25 nm. The C-dots produced a fluorescent emission at wavelength 441 nm. Toxicity tests demonstrate that zebrafish embryo were able to tolerate the C-dots for 48 h after exposure. This study has successfully demonstrated a novel approach of converting GS into excellent fluorescent C-dot.

C15H15N3O3Se, triclinic, P1̅ (no. 2), a = 9.5686(7) Å, b = 12.3795(9) Å, c = 14.7854(11) Å, α = 93.844(2)°, β = 106.344(2)°, γ = 110.816(2)°, V = 1543.4(2) Å3, Z = 4, R gt(F) = 0.0489, wR ref(F 2) = 0.1066, T = 300 K.

A new thiourea compound, 2,2-oxybis(ethyl)-4-(1-naphthyl)-3-thiourea 3 has been synthesized and characterized by using FTIR, 1 H-NMR, 13 C-NMR, and MS spectroscopy. The binding properties of with various cations were also carried out using ‘naked eye’, UV-vis and 1 H-NMR titration experiments. This compound exhibited effective binding for Hg 2+ in the presence of other cations, such as Ag + , Ni 2+ , Sn 2+ , Zn 2+ , Fe 2+ , Cu 2+, and Pb 2+ . Continuous variation titration experiments were conducted in order to determine the binding behavior for Hg 2+ . Stoichiometry of the host and guest binding interactions were also determined using continuous variation titration experiments and plotting molar-ratio curves. Pearson Product moment method was employed to calculate the correlation coefficient, and non-linear regression equation was used to calculate dissociation constant K d . Molar-ratio and binding constant data substantiated the presence of binding sites for the compound 3 .

A new thiourea derivative, N1,N3-bis[[3,5-bis(trifluoromethyl)phenyl]carbamothioyl]isophthalamide (TPC), as a potential copper ionophore was investigated. TPC was immobilized via drop casting method into poly(n-butyl acrylate) pBA membrane and the sensor was characterized by potentiometric method. The sensor fabricated based on TPC showed a Nernstian response towards copper ion with the slope of 27.07±2.84 mV/decade in the range of 1.0×10-6 - 1.0-10-4 M and limit of detection of 6.24 × 10-7 M. In addition, based on the separate solution method (SSM), the logarithm selectivity coefficients were less than -3.00 for monovalent, divalent and trivalent cations that are present in the environmental water samples such as K+, Ca2+, Mg2+ and Fe3+. This confirmed that the sensor fabricated with TPC exhibited good sensitivity and selectivity towards copper ion.A new thiourea derivative, N1,N3-bis[[3,5-bis(trifluoromethyl)phenyl]carbamothioyl]isophthalamide (TPC), as a potential copper ionophore was investigated. TPC was immobilized via drop casting method into poly(n-butyl acrylate) pBA membrane and the sensor was characterized by potentiometric method. The sensor fabricated based on TPC showed a Nernstian response towards copper ion with the slope of 27.07±2.84 mV/decade in the range of 1.0×10-6 - 1.0-10-4 M and limit of detection of 6.24 × 10-7 M. In addition, based on the separate solution method (SSM), the logarithm selectivity coefficients were less than -3.00 for monovalent, divalent and trivalent cations that are present in the environmental water samples such as K+, Ca2+, Mg2+ and Fe3+. This confirmed that the sensor fabricated with TPC exhibited good sensitivity and selectivity towards copper ion.

The building blocks for synthesis of light harvesting antenna which are 5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolane)-10,20-diphenylporphyrin, 5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolane)-10,20-dihexylporphyrin and 5,10,15,20-tetra-(bromophenyl)porphyrin were synthesized. Borylated porphyrin was synthesized by Suzuki coupling reaction between A2BC bromo-porphyrin and pinacolborane. Whereas 5,10,15,20-tetra-(bromophenyl) porphyrin was synthesized by Lindsey condensation reaction between pyrrole and 4-bromobenzaldehyde. 1H-NMR, 13C-NMR spectroscopy and UV-visible spectroscopy confirmed the successful formation of all compounds.The building blocks for synthesis of light harvesting antenna which are 5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolane)-10,20-diphenylporphyrin, 5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolane)-10,20-dihexylporphyrin and 5,10,15,20-tetra-(bromophenyl)porphyrin were synthesized. Borylated porphyrin was synthesized by Suzuki coupling reaction between A2BC bromo-porphyrin and pinacolborane. Whereas 5,10,15,20-tetra-(bromophenyl) porphyrin was synthesized by Lindsey condensation reaction between pyrrole and 4-bromobenzaldehyde. 1H-NMR, 13C-NMR spectroscopy and UV-visible spectroscopy confirmed the successful formation of all compounds.

A Diels-Alder reaction between anthracene and 1-p-tolyl-2,5-dione was conducted in imidazolium-based ionic liquids. Imidazolium cation was utilised with counter anions, [BF 4 ] and [PF 6 ], as the solvents to carry out the desired Diels-Alder reaction. In this work, the diene and dienophile were introduced into the ionic liquids for 72 hours at room temperature. The desired cycloadduct was prepared by a green chemistry procedure in high yield. The expected cycloadduct was characterized on the MS as well as FTIR and NMR spectroscopy. Herein we report, only the [Bmim][BF4] ionic liquid gave the desired cycloadduct in 86 % yield compared to [Bmim][PF 6 ].

A new route to the synthesis of maleimide is described. 2-(2,5-dioxo-2,5-dihydro-1H-pyrrol-1-yl)acetic acid maleimide (1) and 2-(4-(2,5-Dioxo-2,5-dihydro- 1H-pyrrol-1-yl)phenyl)ethanoic acid maleimide (2) have been synthesized by the reaction of maleic anhydride with glycine and 4-aminophenyl acetic aicd. Maleimide (1) was synthesized by conventional technique while maleimide (2) was synthesized by microwave method. The compounds were characterized using FT-Infrared (FT-IR), 1H and 13C Nuclear Magnetic Resonance (NMR) spectroscopies and Mass Spectrometry.

The financial support for this work was provided by EPSRC (Grant EP/K503162/1 and EP/E017851/1) and the Ministry for Higher Education Malaysia. Within a small, interconnected reaction network, orthogonal recognition processes drive the assembly and replication of a [2]rotaxane. Rotaxane formation is governed by a central, hydrogen-bonding-mediated binding equilibrium between a macrocycle and a linear component, which associate to give a reactive pseudorotaxane. Both the pseudorotaxane and the linear component undergo irreversible, recognition-mediated 1,3-dipolar cycloaddition reactions with a stoppering maleimide group, forming rotaxane and thread, respectively. As a result of these orthogonal recognition-mediated processes, the rotaxane and thread can act as auto-catalytic templates for their own formation and also operate as crosscatalytic templates for each other. However, the interplay between the recognition and reaction processes in this reaction network results in the formation of undesirable pseudorotaxane complexes, causing thread formation to exceed rotaxane formation in the current experimental system. Nevertheless, in the absence of competitive macrocycle-binding sites, realization of a replicating network favoring formation of rotaxane is possible. Postprint