Novel quinazolinone Derivatives: Design, synthesis and in vivo evaluation as potential agents targeting Alzheimer disease.

Since Alzheimer disease is one of the most prevalent types of dementia with a high mortality and disability rate, so development of multi-target drugs becomes the major strategy for battling AD. This study shows the development of a series of quinazolinone based derivatives as novel, multifunctional anti-AD drugs that exhibit both cholinesterase inhibitoryand anti-inflammatory properties. The preliminary results of the in vitro AChE inhibition activity showed that compounds 4b, 5a, 6f, 6h and 7b were better represented for further evaluation. Furthermore, in-vivo AChE inhibition activity and behavior Morris water maze test against donepezil as reference drug were evaluated. Additionally, hippocampal inflammatory markers; TNF-α, NFĸB, IL-1ß and IL-6 and antioxidant markers; SOD and MDA were assessed to evaluate the efficacy of quinazolinone derivatives against AD hallmarks. The results showed that 6f, 6h and 7b have promising anti-acetylcholinesterase, anti-inflammatory and antioxidant activities thus, have a significant effect in treatment of AD. Moreover, Histopathological examination revealed that 6f, 6h and 7b derivatives have neuroprotective effect against neuronal damage caused by induced scopolamine model in mice. Finally, the binding ability of the synthesized derivatives to the target, AChE was investigated through molecular docking which reflected significant interactions to the target based on their docking binding scores. Hence, the newly designed quinazolinone derivatives possess promising anti-acetylcholinesterase activity and challenging for the management of AD in the future.

Rationale design of novel substituted 1,3,5-triazine candidates as dual IDH1(R132H)/ IDH2(R140Q) inhibitors with high selectivity against acute myeloid leukemia: In vitro and in vivo preclinical investigations.

In this study, novel substituted 1,3,5-triazine candidates (4a-d, 5a-j, and 6a-d) were designed as second-generation small molecules to act as dual IDH1 and IDH2 inhibitors according to the pharmacophoric features of both vorasidenib and enasidenib. Compounds 6a and 6b for leukemia cell lines showed from low to sub-micromolar GI50. Moreover, compounds 4c, 5f, and 6b described the frontier antitumor activity against THP1 and Kasumi Leukemia cancer cells with IC50 values of (10 and 12), (10.5 and 7), and (6.2 and 5.9) µg/mL, which were superior to those of cisplatin (25 and 28) µg/mL, respectively. Interestingly, compounds 4c, 6b, and 6d represented the best dual IDH1(R132H)/IDH2(R140Q) inhibitory potentials with IC50 values of (0.72 and 1.22), (0.12 and 0.93), and (0.50 and 1.28) µg/mL, respectively, compared to vorasidenib (0.02 and 0.08) µg/mL and enasidenib (0.33 and 1.80) µg/mL. Furthermore, the most active candidate (6b) has very promising inhibitory potentials towards HIF-1α, VEGF, and SDH, besides, a marked increase of ROS was observed as well. Besides, compound 6b induced the upregulation of P53, BAX, Caspases 3, 6, 8, and 9 proteins by 3.70, 1.99, 2.06, 1.73, 1.75, and 1.85-fold changes, respectively, and the downregulation for the BCL-2 protein by 0.55-fold change compared to the control. Besides, the in vivo behavior of compound 6b as an antitumor agent was evaluated in female mice bearing solid Ehrlich carcinoma tumors. Notably, compound 6b administration resulted in a prominent decrease in the weight and volume of the tumors, accompanied by improvements in biochemical, hematological, and histological parameters.

Lead Optimization of BIBR1591 To Improve Its Telomerase Inhibitory Activity: Design and Synthesis of Novel Four Chemical Series with In Silico, In Vitro, and In Vivo Preclinical Assessments.

Herein, modifications to the previously reported BIBR1591 were conducted to obtain bioisosteric candidates with improved activities. The % inhibition of the newly afforded candidates against the telomerase target was investigated. Notably, 6f achieved superior telomerase inhibition (63.14%) compared to BIBR1532 and BIBR1591 (69.64 and 51.58%, respectively). In addition, 8a and 8b showed comparable promising telomerase inhibition with 58.65 and 55.57%, respectively, which were recorded to be frontier to that of BIBR1591. 6f, 8a, and 8b were tested against five cancer cell lines related to the lung and liver subtypes. Moreover, 6f was examined on both cell cycle progression and apoptosis induction in HuH7 cancer cells. Furthermore, the in vivo antitumor activity of 6f was further assessed in female mice with solid Ehrlich carcinoma. In addition, molecular docking and molecular dynamics simulations were carried out. Collectively, 6f, 8a, and 8b could be considered potential new telomerase inhibitors to be subjected to further investigation and/or optimization.

Design and Synthesis of Novel Symmetric Fluorene-2,7-Diamine Derivatives as Potent Hepatitis C Virus Inhibitors.

Hepatitis C virus (HCV) is an international challenge. Since the discovery of NS5A direct-acting antivirals, researchers turned their attention to pursue novel NS5A inhibitors with optimized design and structure. Herein we explore highly potent hepatitis C virus (HCV) NS5A inhibitors; the novel analogs share a common symmetrical prolinamide 2,7-diaminofluorene scaffold. Modification of the 2,7-diaminofluorene backbone included the use of (S)-prolinamide or its isostere (S,R)-piperidine-3-caboxamide, both bearing different amino acid residues with terminal carbamate groups. Compound 26 exhibited potent inhibitory activity against HCV genotype (GT) 1b (effective concentration (EC50) = 36 pM and a selectivity index of >2.78 × 106). Compound 26 showed high selectivity on GT 1b versus GT 4a. Interestingly, it showed a significant antiviral effect against GT 3a (EC50 = 1.2 nM). The structure-activity relationship (SAR) analysis revealed that picomolar inhibitory activity was attained with the use of S-prolinamide capped with R- isoleucine or R-phenylglycine residues bearing a terminal alkyl carbamate group.

Symmetric Anti-HCV Agents: Synthesis, Antiviral Properties, and Conformational Aspects of Core Scaffolds.

As hepatitis C virus (HCV) is one of the major health problems in many countries, interest has been aroused in the design, synthesis, and optimization of novel NS5A inhibitors, outside the chemical space of currently available direct acting antivirals (DAAs). Two series of symmetric molecules with core scaffold 3,3'-(buta-1,3-diyne-1,4-diyl)dianiline or 4,4'-(buta-1,3-diyne-1,4-diyl)dianiline, coupled on its nitrogen as amide with different end caps, were synthesized and tested for their activities against HCV by using cell-based antiviral assays. Molecules with the 3,3'-(buta-1,3-diyne-1,4-diyl)dianiline core were more active than their 4,4'-congeners. Only the 3,3'-derivatives showed noncoplanarity of core phenyls that mostly led to a better interaction with the target protein and appears to be a crucial element for efficient inhibition of HCV replication. Compounds 2f and 2q exhibited potent inhibition of genotype (GT) 1b HCV replication with EC50 values in the picomolar range and selectivity index greater than 6 orders of magnitude. The compounds seem more selective toward GT 1b and 4a. In conclusion, novel symmetric molecules with a 3,3'-(buta-1,3-diyne-1,4-diyl)dianiline core are potent and selective inhibitors that provide new extension to explore the structure-activity relationship of NS5A targeting DAAs.

Genetic similarity of HIV type 1 subtype E in a recent outbreak among injecting drug users in northern Vietnam to strains in Guangxi Province of southern China.

To investigate the molecular epidemiology of a recent HIV-1 outbreak in northern Vietnam and its relation to the epidemic in surrounding areas, we analyzed 17 HIV-positive blood specimens from 3 heterosexuals, 2 sexually transmitted disease patients, and 12 injecting drug users (IDUs), collected in 4 provinces near Hanoi in 1998. These were compared with the specimens from Ho Chi Minh City (n = 10) and An Giang Province (n = 10) in southern Vietnam and with published sequences from neighboring countries. Genetic subtyping based on the env C2/V3 sequences revealed that HIV-1 subtype E predominated throughout Vietnam in all risk populations; the exception was one typical United States-European-type HIV-1 subtype B detected in a patient in Ho Chi Minh City, the first case of HIV infection identified in Vietnam in 1990. The HIV-1 subtype E sequences identified in 9 of the 12 IDUs from northern provinces were closely related phylogenetically to those in IDUs in nearby Guangxi Province of China, and also shared a common amino acid signature downstream of the env V3 loop region. The low interperson nucleotide diversity among IDUs in northern Vietnam supports the view that HIV-1 subtype E was introduced recently among IDUs in northern Vietnam. These data indicate a linkage between HIV-1 circulating among IDUs in northern Vietnam and southern China, and suggest recent transborder introductions as the likely source of HIV-1 subtype E in northern Vietnam.

Nucleotide sequence variation of human T-lymphotropic virus type II in Vietnam.

A high rate of human T-lymphotropic virus type II (HTLV-II) infection has been documented in intravenous drug abusers (IVDAs) in South Vietnam. We have investigated the molecular characteristics of the virus and have shown that one HTLV-II subtype is predominant in Ho Chi Minh City. This molecular subtype, HTLV-IIb, was identified in a number of South Vietnamese by nucleotide sequence analysis of the long terminal repeat (LTR) region. HTLV-IIa was not found. These findings suggest that HTLV-IIb is endemic in IVDAs in South Vietnam, although IVDAs in urban areas in North America are predominantly infected with HTLV-IIa.