Improved synthesis, molecular modeling and anti-inflammatory activity of new fluorinated dihydrofurano-naphthoquinone compounds

A series of new fluorinated dihydrofurano-napthoquinone compounds were sucessfully synthesized in good yields using microwave-assisted multi-component reactions of 2-hydroxy-1,4-naphthoquinone, fluorinated aromatic aldehydes, and pyridinium bromide. The products were fully characterized using spectroscopic techniques and evaluated for their anti-inflammatory activity using lipopolysaccharide (LPS)-stimulated RAW264.7 macrophage cells. Among 12 new compounds, compounds 8b, 8d, and 8e showed high potent NO inhibitory activity in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophage cells with IC50 values ranging from 1.54 to 3.92 µM. The levels of pro-inflammatory cytokines IL-1β and IL-6 in LPS-stimulated RAW264.7 macrophages were remarkably decreased after the application of 8b, 8d, 8e and 8k. Molecular docking simulations revealed structure-activity relationships of 8b, 8d, and 8e toward NO synthase, cyclooxygenase (COX-2 over COX-1), and prostaglandin E synthase-1 (mPGES-1). Further physicochemical and pharmacokinetic computations also demonstrated the drug-like characteristics of synthesized compounds. These findings demonstrated the importance of fluorinated dihydrofurano-napthoquinone moieties in the development of potential anti-inflammatory agents.

Synthesis, in vitro Α-Glucosidase, and acetylcholinesterase inhibitory activities of novel Indol-Fused Pyrano[2,3-D]Pyrimidine compounds

In this study, new indol-fused pyrano[2,3-d]pyrimidines were designed and synthesized. These products were obtained in moderate to good yields and their structures were assigned by NMR, MS, and IR analysis. Afterwards, the biological important of the products was highlighted by evaluating in vitro for α-glucosidase inhibitory activity as well as acetylcholinesterase (AChE) inhibitory activity. Eleven products revealed substantial inhibitory activity against α-glucosidase enzyme, among which, two most potent products 11d,e were approximately 93-fold more potent than acarbose as a standard antidiabetic drug. Besides that, product 11k exhibited good AChE inhibition. The substituents on the 5-phenyl ring, attached to the pyran ring, played a critical role in inhibitory activities. The biological potencies have provided an opportunity to further investigations of indol-fused pyrano[2,3-d]pyrimidines as potential anti-diabetic agents.

Synthesis, molecular docking analysis and in vitro evaluation of new heterocyclic hybrids of 4-aza-podophyllotoxin as potent cytotoxic agents

Two different synthetic approaches to novel heterocyclic hybrid compounds of 4-azapodophyllotoxin were investigated. The obtained products were characterized by infrared spectroscopy, nuclear magnetic resonance spectroscopy, and high-resolution mass spectrometry. MTT protocol was then performed to examine the cytotoxic activity of these products against KB, HepG2, A549, MCF7, and Hek-293 cell lines. The cytotoxic assessment indicated that all products displayed moderate to high cytotoxicity against all tested cancer cell lines. The most active compound 13k containing the 2-methoxypyridin-4-yl group exhibited selective cytotoxicity against KB, A549, and HepG2 cell lines with the IC50 values ranging from 0.23 to 0.27 μM, which were between 5- to 10-fold more potent than the positive control ellipticine. Compounds 13a (HetAr = thiophen-3-yl) and 13d (HetAr = 5-bromofuran-2-yl) displayed high cytotoxic selectivity for A549 and HepG2 cancer cell lines when compared to the other cancer cell lines and low toxicity to the normal Hek-293 cell line. Molecular docking study was conducted to evaluate the interaction of new synthesized compounds with the colchicine-binding-site of tubulin. Besides that, physicochemical and pharmacokinetic properties of the most active compounds 13h,k were predicted.

New-insight UVB Treatment for Psoriasis Vulgaris in Vietnamese Patients

Background

Narrowband UVB (NBUVB) has recently been used in Vietnam for the treatment of psoriasis. However, there are no data on Vietnamese patients to adopt a uniform national protocol.

Objectives

This study aimed to establish an optimal NBUVB therapy for the treatment of psoriasis in Vietnamese patients.

Materials and Methods

One hundred and twenty-two patients with psoriasis vulgaris were included. They were randomly allocated to two groups: the percentage dose (group 1, 62 patients) and the fixed dose (group 2, 60 patients). In group 1, the starting dose was 50% of the minimal erythema dose (MED) and the 10% increment dose adjusted in the next sessions. In group 2, the starting dose was based on Fitzpatrick skin types (fixed dose). Psoriasis area and severity index (PASI) was used to evaluate efficacy.

Results

More than 68% of the patients get PASI75 at session 36. Group 2 had significantly fewer sessions (20 ± 5 vs 25 ± 7, P- value = 0.0004) and lower cumulative dose than group 1 (14.1 ± 4.3 J/cm2 vs 18.0 ± 8.0 J/cm2, P- value = 0.0075) to achieve PASI75. Adverse effects were more common in group 2 than group 1, including burning sensation/erythema (43.33% vs 14.52%, P- value = 0.0009) and pruritus (75.00% vs 22.58%, P- value <0.0001).

Conclusion

NBUVB therapy was safe and effective for Vietnamese psoriasis patients. Fixed doses produced a quicker clinical response with fewer sessions and lower cumulative doses. Adverse effects were mild in both groups and less noted for the MED-based dose. For the recommendation, a fixed dose should be applied for patients who have less concern about side effects, while a MED-based dose can be suitable for patients having conditions related to light sensitivity.

Isolation and genetic characterization of canine distemper virus in domestic dogs from central and northern provinces in Vietnam

Canine distemper virus (CDV) is a pathogen causing fatal disease in a wide range of carnivores. Sequence analysis of CDV strains has been classified into several geographically-related lineages, and the evolution and emergence of these strains are not fully yet investigated. In this study, the complete H gene sequences of 15 CDV strains isolated on Vero DST cell culture from clinical samples of vaccinated domestic dogs in Vietnam were investigated. Fifteen CDV isolates belonging to Asia-1 CDV variants were predominant antigenic type circulated in Central and Northern Vietnam with notable differences regarding the region and some genetic variation, and the most closely related Asia-1 variants lineage reported in Vietnam, China, Taiwan, and Japan. All identified CDV isolates clustered into 2 novel clades Asia-1-C1 and Asia-1-C2. The major amino acid mutation variants of Vietnamese Asia-1 CDV strains were found at sites 51, 157, 159, 160, 171, 178, 186, 235, 245, 277, 288, 313, 324, 330, 337, 345, 358, 359, 365, 383, 446, 475, 517, 530, 584, 598 which include N-glycosylation sites and neutralizing epitope regions in H gene. The results of the virus neutralization titer (VNT) assay showed that the dogs vaccinated with commercial vaccines had significantly low VNT (4.89 and 12.8) against field CDV isolate strains (VNUA NA04, HN18, and NB05) isolated in northern and central Vietnam, respectively. These data may suggest the need for further research in CDV monitoring and development of preventative measures against CDV in Vietnam.

Synthesis and biological activity, and molecular modelling studies of potent cytotoxic podophyllotoxin-naphthoquinone compounds

A new approach for the synthesis of podophyllotoxin-naphthoquinone compounds using microwave-assisted three-component reactions is reported in this study. Novel podophyllotoxin-naphthoquinone derivatives with modification on ring E were synthesized. All the synthetic compounds were assessed in terms of their cytotoxicity profile against four cancer cell lines (KB, HepG2, A549, and MCF7), and noncancerous Hek-293 cell lines. Notably, treatment of SK-LU-1 cells with compounds 5a and 5b resulted in G2/M phase arrest of the cell cycle, caspase-3/7 activation, and apoptosis. Additionally, molecular docking studies were performed and showed important interaction of two compounds against residues in the colchicine-binding-site of tubulin as well. Taken together, compounds 5a and 5b were identified as potent anticancer agents.

A new approach for the synthesis of podophyllotoxin-naphthoquinone compounds using microwave-assisted three-component reactions is reported in this study.

Microwave-Assisted Three-Component Synthesis of Novel N-Arylated-Dihydrobenzo[g]quinoline-5,10-Diones and Their Potential Cytotoxic Activity

A convenient three-component synthetic approach was developed en route to new and significative N-arylated-dihydrobenzo[g]quinoline-5,10-diones using 2-hydroxy-1,4-naphthoquinone, a variety of aromatic aldehydes, and 4-(arylamino)furan-2(5H)-ones. A sequence of steps including Knoevenagel condensation, Michael addition, [1,3]-hydrogen shift, intramolecular cyclization and dehydration led to the formation of products. All the products were structurally characterized by spectroscopic techniques and assessed in terms of their cytotoxicity profile against four cancer cell lines (KB, HepG2, A549, and MCF7), and human embryonic kidney (Hek-293) cell lines.

Synthesis and biological evaluation of novel benzo[a]pyridazino[3,4-c]phenazine derivatives

A convenient microwave-assisted one-pot four-component synthetic approach was developed en route to novel functionalized benzo[a]pyridazino[3,4-c]phenazine derivatives starting from 2-hydroxy-1,4-naphthoquinone, aromatic aldehydes, methyl hydrazine and o-phenylenediamine. Nine new derivatives were successfully synthesized and subsequently evaluated in terms of their biological profiles. The results revealed good cytotoxic activities of compounds 6a, 6h against KB, HepG2, Lu1 and MCF7 human cancer cell lines. Besides that, compound 6d exhibited promising antimicrobial activities toward Staphylococcuc aureus and Bacillus subtilis bacterial strains with IC₅₀ < 6 μM.

The Efficacy of a Two-Fold Increase of H1-Antihistamine in the Treatment of Chronic Urticaria - the Vietnamese Experience

BACKGROUND

Chronic urticaria, a mast cell-driven condition, is common, debilitating and hard to treat. H1-antihistamines are the first line treatment of chronic urticaria, but often patients do not get satisfactory relief with the recommended dose. European guidelines recommend increased antihistamine doses up to four-fold.

AIM

We conducted this study to evaluate the efficacy of increased H1-antihistamine doses up to two-fold in Vietnamese chronic urticaria patients.

METHODS

One hundred and two patients with chronic urticaria were recruited for treatment with levocetirizine (n = 52) or fexofenadine (n = 50). Treatment started at the conventional daily dose of 5 mg levocetirizine or 180 mg fexofenadine for 2 weeks and then increased to 10 mg levocetirizine or 360 mg fexofenadine for 2 weeks if patients did not have an improvement in symptoms. At week 0, week 2 and week 4 wheal, pruritus, size of the wheal, total symptom scores, and associated side-effects were assessed.

RESULTS

With the conventional dose, the total symptom scores after week 2 decreased significantly in both groups compared to baseline figures, i.e. 7.4 vs 2.3 for levocetirizine group and 8.0 vs 2.6 for fexofenadine group (p < 0.05). However, there were still 26 patients in each group who did not have improvements. Of these 26 patients, after having a two-fold increase of the conventional dose, 11.5% and 38.5% became symptom-free at week 4 in levocetirizine group and fexofenadine group, respectively. At week 4 in both groups, the total symptom scores had significantly decreased when compared with those at week 2 (2.8 ± 1.5 versus 4.7 ± 1.6 in levocetirizine group; 2.1 ± 1.9 versus 5.1 ± 1.4 in fexofenadine group). In both groups, there was no difference in the rate of negative side effects between the conventional dose and the double dose.

CONCLUSION

This study showed that increasing the dosages of levocetirizine and fexofenadine by two-fold improved chronic urticaria symptoms without increasing the rate of negative side effects.

Implementation of national action plans on noncommunicable diseases, Bhutan, Cambodia, Indonesia, Philippines, Sri Lanka, Thailand and Viet Nam

By 2016, Member States of the World Health Organization (WHO) had developed and implemented national action plans on noncommunicable diseases in line with the Global action plan for the prevention and control of noncommunicable diseases (2013–2020). In 2018, we assessed the implementation status of the recommended best-buy noncommunicable diseases interventions in seven Asian countries: Bhutan, Cambodia, Indonesia, Philippines, Sri Lanka, Thailand and Viet Nam. We gathered data from a range of published reports and directly from health ministries. We included interventions that addressed the use of tobacco and alcohol, inadequate physical activity and high salt intake, as well as health-systems responses, and we identified gaps and proposed solutions. In 2018, progress was uneven across countries. Implementation gaps were largely due to inadequate funding; limited institutional capacity (despite designated noncommunicable diseases units); inadequate action across different sectors within and outside the health system; and a lack of standardized monitoring and evaluation mechanisms to inform policies. To address implementation gaps, governments need to invest more in effective interventions such as the WHO-recommended best-buy interventions, improve action across different sectors, and enhance capacity in monitoring and evaluation and in research. Learning from the Framework Convention on Tobacco Control, the WHO and international partners should develop a standardized, comprehensive monitoring tool on alcohol, salt and unhealthy food consumption, physical activity and health-systems response.

Synthesis and cytotoxic evaluation of novel indenoisoquinoline-substituted triazole hybrids

The synthesis of various substituted triazole-indenoisoquinoline hybrids was performed based on a CuI-catalyzed 1,3-cycloaddition between propargyl-substituted derivatives and the azide-containing indenoisoquinoline. Besides, a variety of N-(alkyl)propargylindenoisoquinolines was used as substrates for the construction of triazole-indenoisoquinoline-AZT conjugated via a click chemistry-mediated coupling with 3'-azido-3'-deoxythymidine (AZT). Thus, twenty three new indenoisoquinoline-substituted triazole hybrids were successfully prepared and evaluated as cytotoxic agents, revealing an interesting anticancer activity of four triazole linker-indenoisoquinoline-AZT hybrids in KB and HepG2 cancer cell lines.