Phase III, randomized, double-blind, placebo-controlled clinical study: a study on the safety and clinical efficacy of AZVUDINE in moderate COVID-19 patients.

Background: In 2019, a highly pathogenic coronavirus named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) surfaced and resulted in the outbreak of coronavirus disease 2019 (COVID-19). With the aim of finding effective drugs to fight against the disease, several trials have been conducted since COVID-19 can only be considered a treatable disease, from a clinical point of view, after the availability of specific and effective antivirals. AZVUDINE (FNC), initially developed for treating HIV, is a potential treatment for COVID-19 as it has the capability to lower the patient's viral load and promote recovery. Methods: Volunteers infected with SARS-CoV-2 confirmed by reverse transcription polymerase chain reaction (RT-PCR), with good kidney and liver function, who were not using other antivirals or monoclonal antibodies were eligible. Samples from patients were assessed for viral load every 48 h during treatment using reverse transcription quantitative polymerase chain reaction (RT-qPCR) and droplet digital polymerase chain reaction (ddPCR). Results: The study's primary outcome measure was the percentage of participants showing an improvement in clinical scores, while the secondary outcome measure was the percentage of participants with a clinical outcome of cure. These measures were used to assess the safety and efficacy of FNC for treating COVID-19. In the analysis of sociodemographic variables, no significant differences were detected between patients in the FNC and the placebo group for race, age group, or sex. The results showed a potential benefit to participants who received FNC during the study, as observed in the shorter hospital stay, shorter negative conversion time of SARS-CoV-2, and a significant reduction in viral load. Furthermore, the reduction in fever and chills were significant at D1, D2, and D3. In this study, a total of 112 adverse events cases were noted, with 105 cases being categorized as non-serious and only 7 cases as serious adverse events. Conclusion: The pandemic is not being effectively controlled and is causing multiple waves of infection that require extensive medical resources. However, FNC has demonstrated potential to reduce the treatment duration of moderate COVID-19 cases, thereby saving significant medical resources. This makes FNC a promising candidate for COVID-19 treatment.Clinical trial registration: [clinicaltrials.gov], identifier [NCT04668235].

Serial viral load analysis by DDPCR to evaluate FNC efficacy and safety in the treatment of mild cases of COVID-19.

Introduction: The SARS-CoV-2 outbreak has threatened the human population globally as the numbers of reinfection cases even after large-scale vaccination. Trials have been carried out to find drugs effective in fighting the disease, as COVID-19 is being considered a treatable disease only after we have antivirals. A clinical candidate originally developed for HIV treatment, AZVUDINE (FNC), is a promising drug in the treatment of COVID-19. Methods: To predict the clinical outcome of COVID-19, we examined the course of viral load, every 48 h, by RT-PCR, and disease severity using an antiviral drug, FNC, with 281 participants. A randomized clinical trial was performed to evaluate the efficacy of FNC added to standard treatment, compared with placebo group added to standard treatment, for patients with mild COVID-19. RT-qPCR and ddPCR were applied to estimate the viral load in samples from patients. Also, the clinical improvement was evaluated as well as the liver and kidney function. Results and discussion: Notably, the FNC treatment in the mild COVID-19 patients may shorten the time of the nucleic acid negative conversion (NANC) versus placebo group. In addition, the FNC was effective in reducing the viral load of these participants. The present clinical trial results showed that the FNC accelerate the elimination of the virus in and could reduce treatment time of mild patients and save a lot of medical resources, making it a strong candidate for the outpatient and home treatment of COVID-19. Clinical trial registration: https://clinicaltrials.gov/ct2/show/NCT05033145, identifier NCT05033145.

Total synthesis of chondroitin sulfate E oligosaccharides and biological study.

A total synthesis approach of CS-E oligosaccharides was established and a series of derivatives were synthesized. These oligosaccharides were evaluated for a glycosaminoglycan (GAG)-binding protein interaction against cytokines, midkine, and pleiotrophin, by surface-plasmon resonance (SPR) assay. The binding epitopes of oligosaccharides to midkine were mapped using a saturation transfer difference (STD) NMR technique. The groups on the reducing end contributed to binding affinity, and should not be ignored in biological assays. These findings contribute to the structure and activity relationship research and a foundation of understanding that will underpin potential future optimization of this class of oligosaccharides as pharmaceutical agents.

The synthesis and biological evaluation of chondroitin sulfate E glycodendrimers.

Aim: Chondroitin sulfate (CS) is a class of highly sulfated polysaccharides that possess many important biological functions. The heterogeneity of CS limits pharmacological research and leads to ambiguous mechanisms. Thus, glycomimetics are demanded as replacement of natural polysaccharides to explore important biological processes. Results & methodology: Here the preparation of CS glycodendrimers is reported as well as their use as CS mimetics to regulate the NF-κB pathway. Multivalent presentation of sugar epitopes on appropriate dendrimer scaffolds increased the suppression of the NF-κB pathway. The interaction between CS-E molecules and TNF-α was examined by nuclear magnetic resonance technology. Conclusion: Overall, the glycodendrimer reported here may be potentially employed as molecular tool to investigate the biological functions of CS.

ORP4L Extracts and Presents PIP2 from Plasma Membrane for PLCß3 Catalysis: Targeting It Eradicates Leukemia Stem Cells.

Leukemia stem cells (LSCs) are a rare subpopulation of abnormal hematopoietic stem cells (HSCs) that propagates leukemia and are responsible for the high frequency of relapse in therapies. Detailed insights into LSCs' survival will facilitate the identification of targets for therapeutic approaches. Here, we develop an inhibitor, LYZ-81, which targets ORP4L with high affinity and specificity and selectively eradicates LCSs in vitro and in vivo. ORP4L is expressed in LSCs but not in normal HSCs and is essential for LSC bioenergetics and survival. It extracts PIP2 from the plasma membrane and presents it to PLCß3, enabling IP3 generation and subsequent Ca2+-dependent bioenergetics. LYZ-81 binds ORP4L competitively with PIP2 and blocks PIP2 hydrolysis, resulting in defective Ca2+ signaling. The results provide evidence that LSCs can be eradicated through the inhibition of ORP4L by LYZ-81, which may serve as a starting point of drug development for the elimination of LSCs to eventually cure leukemia.

Antibacterial activities of a series of novel 5-O-(4', 6'-O-dimodified)-mycaminose 14-membered ketolides.

A series of novel 5-O-(4',6'-O-dimodified)-mycaminose 14-membered ketolides were assessed for their in vitro antibacterial activities against a panel of sensitive and resistant pathogens. Compound 1 and compound 2, two ester analogs, showed the best antibacterial activities against several macrolide-sensitive and macrolide-resistant strains. These results indicated that introducing ester to 6-OH and a small volume ether substituent to the 4-OH of mycaminose could improve the antibacterial activities of ketolides.

Synthesis and Antibacterial Activity of Novel 4″-O-desosaminyl clarithromycin derivatives with 11, 12-arylalkyl side chains.

A series of novel 4″-O-desosaminyl clarithromycin derivatives with 11, 12-arylalkyl side chains was synthesized by coupling 6-deoxy-desosamine donors (18, 19) with 4″-OH of compounds 5a-c. The activities of the target compounds were tested against a series of macrolide-sensitive and macrolide-resistant pathogens. Some of them showed activities against macrolide sensitive and resistant pathogens, and compounds 21d and 21e displayed significant improvement of activities against resistant pathogens.

Synthesis and antibacterial activity of novel ketolides with 11,12-quinoylalkyl side chains.

A series of quinoylalkyl side chains was designed and synthesized, followed by introduction into ketolides by coupling with building block 6 or 32. The corresponding targets 7a-n, 33b, and 33e were tested for their in vitro activities against a series of macrolide-sensitive and macrolide-resistant pathogens. Some of them showed a similar antibacterial spectrum and comparable activity to telithromycin. Among them, two C2-F ketolides, compounds 33b and 33e, displayed excellent activities against macrolide-sensitive and macrolide-resistant pathogens.

An Approach to Synthesize Chondroitin Sulfate-E (CS-E) Oligosaccharide Precursors.

An approach was developed to synthesize chondroitin sulfate-E (CS-E) oligosaccharides by adopting a postglycosylation-transformation strategy: different from all of the traditional approaches, the characteristic groups of CS-E were introduced following the assembly of the oligosaccharides. The adjusted strategy rendered an easy chain elongation strategy. All of the elongation steps generated high yields with excellent glycosylation outcomes. An orthogonally protected disaccharide was used as the building block to provide flexibility for the group transformation and derivatization at the N-2 position of the GalNAc residue and the O-1,5 positions of the GlcA residue, thereby providing ready access for the further examination of the structure-activity relationship (SAR) of CS-E molecules.

Synthesis and antibacterial activities of some novel 17, 18-unsaturated carbonyl compounds derivated from josamycin.

Some novel josamycin derivatives bearing an arylalkyl-type side chain were designed and synthesized. By HWE or Wittig reaction, 16-aldehyde group of josamycin analogs were converted into unsaturated carbonyl compounds. They were evaluated for their in vitro antibacterial activities against a panel of respiratory pathogens. 8b and 8e exhibited comparable activities against a panel of respiratory pathogens, especially to resistant ones in the series of desmycarosyl josamycin analogs. Among of all the target molecules, 21 showed the best antibacterial activities.

Synthesis and cytotoxic activity of two steroids: icogenin aglycone analogs.

During the process of icogenin analog research, we obtained two cytotoxic steroids: compound 4 and compound 6 casually. Their in vitro antitumor activities were tested by the standard MTT assay. The results disclosed that compound 4 (IC50 = 3.65-6.90 µM) showed potential antitumor activities against HELA, KB cell lines and compound 6 (IC50 = 2.40-9.05 µM) showed potential antitumor activities against HELA, BGC-823, KB, A549, HCT-8 cell lines.

ORP4L is essential for T-cell acute lymphoblastic leukemia cell survival.

Metabolic pathways are reprogrammed in cancer to support cell survival. Here, we report that T-cell acute lymphoblastic leukemia (T-ALL) cells are characterized by increased oxidative phosphorylation and robust ATP production. We demonstrate that ORP4L is expressed in T-ALL but not normal T-cells and its abundance is proportional to cellular ATP. ORP4L acts as an adaptor/scaffold assembling CD3ɛ, Gαq/11 and PLCß3 into a complex that activates PLCß3. PLCß3 catalyzes IP3 production in T-ALL as opposed to PLCγ1 in normal T-cells. Up-regulation of ORP4L thus results in a switch in the enzyme responsible for IP3-induced endoplasmic reticulum Ca(2+) release and oxidative phosphorylation. ORP4L knockdown results in suboptimal bioenergetics, cell death and abrogation of T-ALL engraftment in vivo. In summary, we uncovered a signalling pathway operating specifically in T-ALL cells in which ORP4L mediates G protein-coupled ligand-induced PLCß3 activation, resulting in an increase of mitochondrial respiration for cell survival. Targeting ORP4L might represent a promising approach for T-ALL treatment.

Synthesis of three OSW-1 analogs with maltose side chains bearing different protection groups.

In order to simplify the synthesis of OSW-1's disaccharide side chain and explore the structure-activity relationship of OSW-1, three 16α-O-maltose OSW-1 analogs carrying three maltose side chains bearing different protections were designed and synthesized.

Synthesis and antibacterial activity of a series of novel 9-O-acetyl- 4'-substituted 16-membered macrolides derived from josamycin.

A series of novel 9-O-acetyl-4'-substituted 16-membered macrolides derived from josamycin has been designed and synthesized by cleavage of the mycarose of josamycin and subsequent modification of the 4'-hydroxyl group. These derivatives were evaluated for their in vitro antibacterial activities against a panel of Staphylococcus aureus and Staphylococcus epidermidis. 15 (4'-O-(3-Phenylpropanoyl)-9-O-acetyl-desmycarosyl josamycin) and 16 (4'-O-butanoyl-9-O-acetyl-desmycarosyl josamycin) exhibited comparable activities to josamycin against S. aureus (MSSA) and S. epidermidis (MSSE).

Synthesis of 4″-O-desosaminyl clarithromycin derivatives and their anti-bacterial activities.

A series of new 4″-O-desosaminyl clarithromycin derivatives were designed and synthesized. The efficient synthesis routes of 6-deoxy-desosamine donors 8 and 11 were developed and the methodology of glycosylation of clarithromycin 4″-OH with desosamine was studied. The activities of the target compounds were tested against a series of macrolide-sensitive and macrolide-resistant pathogens. Some of them showed activities against macrolide sensitive pathogens, and compounds 19 and 22 displayed significant improvement of activities against sensitive pathogens and two strains of MRSE, which verified the importance of desosamine in the interaction of macrolide and its receptor, and offered valuable information of the SAR of macrolide 4″-OH derivatives.

Synthesis and antibacterial activity of novel modified 5-O-mycaminose 14-membered ketolides.

A practicable method of introducing a side chain to the C-4' position of 5-O-desosamine in the 14-membered ketolides was developed. And using this method, a series of novel modified 5-O-mycaminose ketolides were synthesized. These ketolides containing 5-O-4'-carbamate mycaminose were evaluated for their in vitro antibacterial activities against some respiratory pathogens. 15b and 18e showed comparable activity to telithromycin and clarithromycin.

Synthesis and antibacterial activity of novel modified 5-O-desosamine ketolides.

A series of novel modified 5-O-desosamine-ketolides were synthesized. The 5-O-desosamine fragment was removed from ketolide by an efficient and mild manipulation. 4-O-substituted desosamine was introduced into the ketolide aglycon and various coupling methods were essayed for the glycosylation. Three novel ketolides were tested for in vitro antibacterial activity against a panel of susceptible and resistant pathogens. Compound 26 showed potent activity against all the methicillin-sensitivity and resistant pathogens.

Synthesis and antitumor activity of 5,6-dihydro-17-hydroxy icogenin analogs.

Four 5,6-dihydro-17-hydroxy icogenin analogs were designed and synthesized. Their in vitro antitumor activities were tested by the standard MTT assay. Compound 22 (IC(50) = 3.38-8.30 µM) and compound 23 (IC(50) = 1.90-9.69 µM) showed potential antitumor activities against the entire tested seven cancer cell lines. The SAR (structure activity relationship) research showed that the introduction of 17-hydroxy lowered the antitumor activity to an extent.

Synthesis of cholestane saponins as mimics of OSW-1 and their cytotoxic activities.

To fulfill the structure-activity relationship (SAR) of OSW-1, and aim at finding the simplest structural part while maintaining most of the biological activities, six cholestane saponins were synthesized by introducing OSW-1 disaccharide (2-O-4-methoxybenzoyl-ß-D-xylopyranosyl-(1→3)-2-O-acetyl-α-L-arabinopyranosyl) and its 1→4-linked analogue to the 7-hydroxy or 16-hydroxy of steroidal sapogenins. Cytotoxic activities of the products were tested. Compounds 1 and 3 exhibited potent cytotoxicities against five types of human tumor cells, with minimum IC(50) of 2.0 and 75 nM, respectively. And due to its high activity and easy accessibility compound 1 could be a potential candidate for new anti-tumor agents.