Titel Deelnemers "Korte inhoud" "Structure-based design of diarylpyrimidines and triarylpyrimidines as potent HIV-1 NNRTIs with improved metabolic stability and drug resistance profiles." "Christophe Pannecouque" "Non-nucleoside reverse transcriptase inhibitors (NNRTIs) are an important component of anti-acquired immunodeficiency syndrome treatment regimen. In the present work, with the previously reported compound K-16c as lead, a series of novel 2,4,5-trisubstituted pyrimidine derivatives were designed based on the cocrystal structure of K-16c/RT, with the aim to improve the anti-human immunodeficiency virus type-1 (HIV-1) activities and metabolic stability properties. Compound 11b1 exhibited the most potent antiviral activity against wild-type (WT) and a panel of single mutant HIV-1 strains (EC50  = 2.4-12.4 nM), being superior to or comparable to those of the approved drug etravirine. Meanwhile, 11b1 exhibited moderate cytotoxicity (CC50  = 4.96 μM) and high selectivity index (SI = 1189) toward HIV-1 WT strain. As for HIV-1 RT inhibition test, 11b1 possessed excellent inhibitory potency (IC50  = 0.04 μM) and confirmed its target was RT. Moreover, the molecular dynamics simulation was performed to elucidate the improved drug resistance profiles. Moreover, 11b1 was demonstrated with favorable safety profiles and pharmacokinetic properties in vivo, indicating that 11b1 is a potential anti-HIV-1 drug candidate worthy of further development." "Structure-based design and optimization lead to the identification of novel dihydrothiopyrano[3,2-d]pyrimidine derivatives as potent HIV-1 inhibitors against drug-resistant variants." "Christophe Pannecouque" "With our continuous endeavors in seeking potent anti-HIV-1 agents, we reported here the discovery, biological characterization, and druggability evaluation of a class of nonnucleoside reverse transcriptase inhibitors. To fully explore the chemical space of the NNRTI-binding pocket, novel series of dihydrothiopyrano [3,2-d]pyrimidines were developed by employing the structure-based design strategy. Most of the derivatives were endowed with prominent antiviral activities against HIV-1 wild-type and resistant strains at nanomolar levels. Among them, compound 23h featuring the aminopiperidine moiety was identified as the most potent inhibitor, with EC50 values ranging from 3.43 to 21.4 nmol/L. Especially, for the challenging double-mutants F227L + V106A and K103N + Y181C, 23h exhibited 2.3- to 14.5-fold more potent activity than the first-line drugs efavirenz and etravirine. Besides, the resistance profiles of 23h achieved remarkable improvement compared to efavirenz and etravirine. The binding target of 23h was further confirmed to be HIV-1 reverse transcriptase. Molecular modeling studies were also performed to elucidate the biological evaluation results and give guidance for the optimization campaign. Furthermore, no apparent inhibition of the major CYP450 enzymes and hERG channel was observed for 23h. Most importantly, 23h was characterized by good pharmacokinetic properties and excellent safety in vivo. Collectively, 23h holds great promise as a potential candidate for its effective antiviral efficacy and favorable drug-like profiles." "Selected Milestones in Antiviral Drug Development." "Erik De Clercq" "This review article will describe the (wide) variety of approaches that I envisaged to develop a specific therapy for viral infections: (i) interferon and its inducers, (ii) HSV, VZV and CMV inhibitors, (iii) NRTIs (nucleoside reverse transcriptase inhibitors), NtRTIs (nucleotide reverse transcriptase inhibitors) and NNRTIs (non-nucleoside reverse transcriptase inhibitors) as HIV inhibitors, (iv) NtRTIs as HBV inhibitors, and finally, (v) the transition of an HIV inhibitor to a stem cell mobilizer, as exemplified by AMD-3100 (Mozobil®)." "In situ click chemistry-based discovery of 1,2,3-triazole-derived diarylpyrimidines as novel HIV-1 NNRTIs by exploiting the tolerant region I in binding pocket" "Erik De Clercq, Christophe Pannecouque" "HIV-1 reverse transcriptase (RT) is considered as one of the most significant targets for the anti-HIV-1 drug design due to their determined mechanism and well-decoded crystal structure. As a part of our continuous efforts towards the development of potent HIV-1 non-nucleoside reverse transcriptase inhibitors (NNRTIs) by exploiting the tolerant region I of NNRTIs binding pocket (NNIBP), the miniaturized parallel synthesis via CuAAC click chemistry reaction followed by in situ biological screening have been performed in this work. The in situ enzyme inhibition screening results showed that 14 compounds exhibited higher or equivalent inhibitory activity compared to the lead K-5a2 and ETR. Anti-HIV-1 activity results indicated that C1N51 displayed the most potent activity (EC50 = 0.01-0.26 μM) against wild-type and a panel of NNRTIs-resistant strains. Moreover, the molecular simulation demonstrated that the newly introduced triazole ring could develop new hydrogen bonds with Lys103 and Pro236, which explained the feasibility of introducing triazole in the tolerant region I of the RT binding pocket." "Discovery, Crystallographic Studies, and Mechanistic Investigations of Novel Phenylalanine Derivatives Bearing a Quinazolin-4-one Scaffold as Potent HIV Capsid Modulators" "Erik De Clercq, Christophe Pannecouque" "Optimization of compound 11L led to the identification of novel HIV capsid modulators, quinazolin-4-one-bearing phenylalanine derivatives, displaying potent antiviral activities against both HIV-1 and HIV-2. Notably, derivatives 12a2 and 21a2 showed significant improvements, with 2.5-fold over 11L and 7.3-fold over PF74 for HIV-1, and approximately 40-fold over PF74 for HIV-2. The X-ray co-crystal structures confirmed the multiple pocket occupation of 12a2 and 21a2 in the binding site. Mechanistic studies revealed a dual-stage inhibition profile, where the compounds disrupted capsid-host factor interactions at the early stage and promoted capsid misassembly at the late stage. Remarkably, 12a2 and 21a2 significantly promoted capsid misassembly, outperforming 11L, PF74, and LEN. The substitution of easily metabolized amide bond with quinolin-4-one marginally enhanced the stability of 12a2 in human liver microsomes compared to controls. Overall, 12a2 and 21a2 highlight their potential as potent HIV capsid modulators, paving the way for future advancements in anti-HIV drug design." "Structure-based design of novel heterocycle-substituted ATDP analogs as non-nucleoside reverse transcriptase inhibitors with improved selectivity and solubility" "Christophe Pannecouque, Erik De Clercq" "Following on our recently developed biphenyl-ATDP non-nucleoside reverse transcriptase inhibitor ZLM-66 (SI = 2019.80, S = 1.9 μg/mL), a series of novel heterocycle-substituted ATDP derivatives with significantly improved selectivity and solubility were identified by replacement of the biphenyl moiety of ZLM-66 with heterocyclic group with lower lipophilicity. Evidently, the representative analog 7w in this series exhibited dramatically enhanced selectivity and solubility (SI = 12,497.73, S = 4472 μg/mL) in comparison with ZLM-66 (SI = 2019.80, S = 1.9 μg/mL). This new NNRTI conferred low nanomolar inhibition of wild-type HIV-1 strain and tested mutant strains (K103N, L100I, Y181C, E138K, and K103N + Y181C). The analog also demonstrated favorable safety and pharmacokinetic profiles, as evidenced by its insensitivity to CYP and hERG, lack of mortality and pathological damage, and good oral bioavailability in rats (F = 27.1%). Further development of 7w for HIV therapy will be facilitated by this valuable information." "Structure-directed expansion of biphenyl-pyridone derivatives as potent non-nucleoside reverse transcriptase inhibitors with significantly improved potency and safety" "Christophe Pannecouque" "4-Phenylcoumarin derivatives as new HIV-1 NNRTIs: Design, synthesis, biological activities, and computational studies" "Christophe Pannecouque" "A series of 4-phenylcoumarin derivatives was synthesized and evaluated for their cellular anti-HIV-1 and HIV-2 activities as well as their inhibitory effects against HIV-1 reverse transcriptase (RT). The hydrazone compound 8b and the ethylthiosemicarbazide derivative 4c showed the best inhibition activity against wild-type (WT) HIV-1. The promising compounds were further evaluated against HIV-1 RT and exhibited significant inhibitory activity with compound 8b showing comparable effect to the reference NNRTI Efavirenz (IC50 = 9.01 nM). Structure activity relationship study revealed the importance of 6-chloro and 4-phenyl substituents for optimum activity, as well as the 5-atoms linker (=N-NH-CO-CH2-O-) at position 7 of coumarin scaffold that can support the rotation and flexibility of compound 8b to fit well in the binding pocket. The molecular docking of compound 8b demonstrated a typical seahorse binding mode with better binding interactions that covered more residues when compared to Efavirenz." "A new alkaloid from Pancratium maritimum - Structure elucidation using computer-assisted structure elucidation (CASE) and evaluation of cytotoxicity and anti-SARS-CoV-2 activity" "Steven De Jonghe, Johan Neyts, Christophe Pannecouque" "5-Cyano substituted diarylpyridines as potent HIV-1 NNRTIs: Rational design, synthesis, and activity evaluation" "Erik De Clercq, Christophe Pannecouque" "To develop more potent HIV-1 inhibitors against a variety of NNRTIs-resistant strains, a series of 5-cyano substituted diarylpyridines was designed based on the cocrystal structural analysis. Among them, I-5b showed the greatest potency (EC50 = 5.62-171 nM) against the wild-type (WT) and mutant HIV-1 strains. Especially for K103 N, I-5b exhibited outstanding activity with EC50 values of 9.37 nM, being much superior to that of NVP (EC50 = 5128 nM) and EFV (EC50 = 114 nM) and comparable to that of ETR (EC50 = 3.45 nM). In addition, the target of all compounds was turned out to be HIV-1 RT with moderate RT enzyme inhibitory activity (IC50 = 0.094-12.0 μM). Moreover, the binding mode of representative compounds with RT was elaborated via molecular docking."