Chemistry via Carnival: An Activity Based Approach in Learning Chemistry(Pembelajaran Kimia melalui Karnival: Pendekatan Pembelajaran Kimia Berasaskan Aktiviti)

This paper reports the experience of activity based learning conducted in Chemistry Carnival 2011 in Sarawak. The active learning oriented activities include hands-on experiments, quiz, poster and mini lectures were used to educate the school students some basics chemistry relating to daily life. Approximately 300 students attended the activities. Observations and questionnaires were used as the instruments to describe and measure the learning experience whether various activities have contributed to effective learning. Among these, hands-on experiments were found to be the most effective approach; more than 86% of the participants agree that they have learnt well from this peer mentoring and collaborative learning strategy. Posters, mini lectures and quiz however were relatively less favoured as they suffered some inherited shortcomings for example lecture is lacking in interactivity, poster and quiz similarly fall short in proactive involvement of participants. Activity based learning is an effective approach however it needs to be carefully constructed to achieve the learning outcomes

Synthesis and anticancer activities of 4-[(Halophenyl)diazenyl]phenol and 4-[(Halophenyl)diazenyl]phenyl aspirinate derivatives against nasopharyngeal cancer cell lines

Aspirin and azo derivatives have been widely studied and have drawn considerable attention due to diverse biological activities. In this study, a series of 4-[(halophenyl)diazenyl]phenyl aspirinate derivatives were synthesized from the reaction of aspirin with 4-[(halophenyl)diazenyl] phenol via esterification, in the presence of DCC/DMAP in DCM with overall yield of 45-54%. 4-[(Halophenyl)diazenyl]phenol was prepared prior to esterification from coupling reaction of aniline derivatives and phenol in basic solution. All compounds were characterized using elemental analysis, FTIR, and 1 H and 13 C NMR spectroscopies. All compounds were screened for their anticancer activities against nasopharyngeal cancer (NPC) HK-1 cell lines and the viability of cultured cells was determined by MTS [3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxylmethoxylphenyl)-2-(4-sulfophenyl)-2H-tetrazolium]-based colorimetric assay. 4-[(E)-(Fluorophenyl)diazenyl] phenol showed the highest anticancer activity against NPC HK-1 cell lines compared to other synthesized compounds. 4-[(Halophenyl)diazenyl]phenyl aspirinate showed low cytotoxicity against NPC HK-1 cell lines compared to 4-[(halophenyl)diazenyl] phenol but better anticancer activity than aspirin alone. © 2017 Boon Kui Ho et al

Synthesis and anticancer activities of 4-[(Halophenyl)diazenyl]phenol and 4-[(Halophenyl)diazenyl]phenyl aspirinate derivatives against nasopharyngeal cancer cell lines

Aspirin and azo derivatives have been widely studied and have drawn considerable attention due to diverse biological activities. In this study, a series of 4-[(halophenyl)diazenyl]phenyl aspirinate derivatives were synthesized from the reaction of aspirin with 4-[(halophenyl)diazenyl] phenol via esterification, in the presence of DCC/DMAP in DCM with overall yield of 45-54%. 4-[(Halophenyl)diazenyl]phenol was prepared prior to esterification from coupling reaction of aniline derivatives and phenol in basic solution. All compounds were characterized using elemental analysis, FTIR, and 1 H and 13 C NMR spectroscopies. All compounds were screened for their anticancer activities against nasopharyngeal cancer (NPC) HK-1 cell lines and the viability of cultured cells was determined by MTS [3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxylmethoxylphenyl)-2-(4-sulfophenyl)-2H-tetrazolium]-based colorimetric assay. 4-[(E)-(Fluorophenyl)diazenyl] phenol showed the highest anticancer activity against NPC HK-1 cell lines compared to other synthesized compounds. 4-[(Halophenyl)diazenyl]phenyl aspirinate showed low cytotoxicity against NPC HK-1 cell lines compared to 4-[(halophenyl)diazenyl] phenol but better anticancer activity than aspirin alone. © 2017 Boon Kui Ho et al

In vitro cytotoxicity evaluation of thiourea derivatives bearing Salix sp. constituent against HK-1 cell lines

In searching for drugs from natural product scaffolds has gained interest among researchers. In this study, a series of twelve halogenated thiourea (ATX 1-12)via chemical modification of aspirin (a natural product derivative) and evaluated for cytotoxic activity against nasopharyngeal carcinoma (NPC) cell lines, HK-1 via MTS-based colorimetric assay. The cytotoxicity studies demonstrated that halogens at meta position of ATX showed promising activity against HK-1 cells (IC 50 value ≤15 µM) in comparison to cisplatin, a positive cytotoxic drug (IC 50 value =8.9 ± 1.9 µM). ATX 11, bearing iodine at meta position, showed robust cytotoxicity against HK-1 cells with an IC 50 value of 4.7 ± 0.7 µM. Molecular docking interactions between ATX 11 and cyclooxygenase-2 demonstrated a robust binding affinity value of −8.1 kcal/mol as compared to aspirin’s binding affinity value of −6.4 kcal/mol. The findings represent a promising lead molecule from natural product with excellent cytotoxic activity against NPC cell lines. © 2018, © 2018 Informa UK Limited, trading as Taylor & Francis Group