The pyridine ring is a potent pharmacophore in alkaloid natural products. Nonetheless, its biosynthetic pathways are poorly understood. Rubrolones A and B are tropolone alkaloid natural products possessing a unique tetra-substituted pyridine moiety. Here, we report the gene cluster and propose a biosynthetic pathway for rubrolones, identifying a key intermediate that accumulates upon inactivation of sugar biosynthetic genes. Critically, this intermediate was converted to the aglycones of rubrolones by non-enzymatic condensation and cyclization with either ammonia or anthranilic acid to generate the respective pyridine rings. We propose that this non-enzymatic reaction occurs via hydrolysis of the key intermediate, which possesses a 1,5-dione moiety as an amine acceptor capable of cyclization. This study suggests that 1,5-dione moieties may represent a general strategy for pyridine ring biosynthesis, and more broadly highlights the utility of non-enzymatic diversification for exploring and expanding natural product chemical space.
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http://dx.doi.org/10.1038/ncomms13083 | DOI Listing |
J Agric Food Chem
January 2025
Institute of Applied Chemistry, Jiangxi Academy of Sciences, Nanchang 330096, China.
Taking the natural product cerbinal as the lead compound, 30 novel 5-aryl-cyclopenta[]pyridine derivatives were designed and synthesized based on the previous bioactivity studies of the cyclopenta[]pyridines. The modification of the position-5 of compound was achieved by amination, bromination, and cross coupling using cerbinal as the raw material. The results of the bioactivity tests demonstrated that partial compounds exhibited superior activity against plant viruses compared to compound .
View Article and Find Full Text PDFTop Antivir Med
August 2024
New York Blood Center, New York, New York, USA.
Data on the HIV care cascade demonstrated challenges in achieving Ending the HIV Epidemic (EHE) targets across all 18 EHE focus metropolitan areas, but innovative adherence interventions using point-of-care tenofovir testing and motivational interviewing support care cascade outcomes in Namibia and South Africa, respectively. Data on treatment with long-acting injectable (LAI) antiretroviral therapy (ART) demonstrated high acceptability, retention, and virologic suppression including in groups that were not well represented in clinical trials including persons born female and persons with detectable viral loads. The adjuvanted hepatitis B vaccine appeared to be safe and appeared to be superior to conventional hepatitis B vaccines in persons with HIV (PWH) who were prior nonresponders to the hepatitis B vaccine.
View Article and Find Full Text PDFJ Acquir Immune Defic Syndr
October 2024
Harvard TH Chan School of Public Health, Boston, MA, USA.
Introduction: Women with HIV (WHIV) have higher risks of adverse pregnancy outcomes, particularly in the absence of antiretroviral treatment(ART), and timing of ART may impact risk.
Methods: In IMPAACT 2010 (VESTED), 643 pregnant WHIV in 9 countries were randomized 1:1:1 to initiate ART: dolutegravir (DTG)+emtricitabine(FTC)/tenofovir alafenamide(TAF); DTG+FTC/tenofovir disoproxil fumarate (TDF) or efavirenz (EFV)/FTC/TDF. We describe adverse pregnancy outcomes in women with a subsequent pregnancy during 50 weeks of postpartum follow-up: spontaneous abortion (<20 weeks), stillbirth (≥20 weeks), preterm delivery (<37 weeks) and small-for-gestational-age (SGA).
Eur J Med Chem
December 2024
School of Pharmaceutical Sciences, Lovely Professional University, Phagwara, 144411, India. Electronic address:
This study presents a comprehensive exploration of the synthesis of novel compounds targeting Chagas Disease (CD) caused by Trypanosoma cruzi. It is a global health threat with over 6-7 million infections worldwide. Addressing challenges in current treatments, the investigation explores diverse compound classes, including thiazoles, thiazolidinone, imidazole, pyrazole, 1,6-diphenyl-1H-pyrazolo[3,4-b] pyridine, pyrrole, naphthoquinone, neolignan, benzeneacyl hydrazones, and chalcones-based compounds.
View Article and Find Full Text PDFArch Pharm (Weinheim)
January 2025
School of Chemistry and Pharmaceutical Engineering, Huanghuai University, Zhumadian, Henan, China.
Cancer, characterized by uncontrolled growth and spread of abnormal cells potentially influencing almost all tissues in the body, is one of the most devastating and lethal diseases throughout the world. Chemotherapy is one of the principal approaches for cancer treatment, but multidrug resistance and severe side effects represent the main barriers to the success of therapy, creating a vital need to develop novel chemotherapeutic agents. The 1,2,3-triazole moiety can be conveniently constructed by "click chemistry" and could exert diverse noncovalent interactions with various enzymes in cancer cells.
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