Naturally Occurring Lumazines

Daniels, Benjamin; Li, Freda F.; Furkert, Daniel P.; Brimble, Margaret A.

doi:10.1021/acs.jnatprod.9b00351

Cited by 8 publications

(4 citation statements)

References 123 publications

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“…Lumazine peptides are a small class of natural products . So far, only a dozen such compounds have been isolated from natural sources. ,,− Biogenetically, compounds 1 and 2 could be derived from lumazine acid, alanine, and anthranilic acid, while 3 , 4 , 5 , and 8 could be derived from lumazine-6-carboxylic acid, serine or glutamine, or methionine sulfoxide, respectively, and anthranilic acid . It is also possible that compound 1 was derived from compound 2 and glycine.…”

Section: Resultsmentioning

confidence: 99%

Antibacterial and NF-κB Inhibitory Lumazine Peptides, Aspochalasin, γ-Butyrolactone Derivatives, and Cyclic Peptides from a Hawaiian Aspergillus flavipes

Bai

Zaman

et al. 2020

J. Nat. Prod.

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Five new lumazine peptides (1–5), a new aspochalasin derivative (6), and a new γ-butyrolactone derivative (7), together with seven known compounds (8–14), were isolated from a Hawaiian fungal strain, Aspergillus flavipes FS888. Compound 1 is an uncommon natural product containing an isocyano group. The structures of the new compounds 1–7 were elucidated by NMR spectroscopy, HRESIMS, chemical derivatization, and ECD analysis. Compounds 12–14 showed significant antibacterial activity against S. aureus when in combination with disulfiram. Additionally, compounds 9 and 13 showed NF-κB inhibitory activity with IC50 values of 3.1 ± 1.0 and 10.3 ± 2.0 μM, respectively.

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Section: Resultsmentioning

confidence: 99%

Antibacterial and NF-κB Inhibitory Lumazine Peptides, Aspochalasin, γ-Butyrolactone Derivatives, and Cyclic Peptides from a Hawaiian Aspergillus flavipes

Bai

Zaman

et al. 2020

J. Nat. Prod.

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“…Pteridines are low molecular weight organic compounds consisting of fused pyrazine and pyrimidine rings [1]. Pteridines can be divided into two groups based on their structure: pterins and lumazines.…”

Section: Introductionmentioning

confidence: 99%

Dilute-and-Shoot-Liquid Chromatography-Quadrupole Time of Flight-Mass Spectrometry for Pteridine Profiling in Human Urine and Its Association with Different Pathologies

et al. 2023

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Pteridines are a group of compounds synthesised by many living organisms that are involved in the metabolism of many cofactors and vitamins. Their concentration in biological fluids may be altered by various pathologies such as cancer or inflammatory bowel disease, urine being the main route of excretion. In this study, three lumazines and ten pterins were analysed in their native oxidation state using high-performance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry. Their high concentration in urine samples and their good ionisation behaviour allow the use of the dilute-and-shoot method by simple filtration of the urine prior to chromatographic analysis. The final method offers excellent linearity, sensitivity and precision parameters, and a total of 135 urine samples were analysed from patients with some relevant information such as faecal calprotectin (FCP) levels, common diseases such as diabetes, hypertension and dyslipidaemia and immunological diseases such as inflammatory bowel disease (IBD). The pteridine profile was related to FCP levels without showing any correlation. In addition, pteridine levels were compared between healthy subjects and IBD, diabetic, hypertensive and dyslipidaemic patients, and significant differences were found between the two groups for some of the pteridines.

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“…More than 70 years after its first synthesis, 1 was recognized as a natural product and isolated from male ants of the species Formica polyctena (Schmidt and Viscontini, 1967) and more recently also from the leaves of Brassica juncea L. (brown mustard) (Sharma et al, 2018). Unsubstituted lumazine (1) is not widely distributed in nature (Daniels et al, 2019); related compounds substituted at positions 6, 7 and 8 are of greater biological significance. Importantly, 6,7-dimethyl-8-ribityllumazine (2) is the direct biosynthetic precursor of riboflavin (4; vitamin B 2 ) (Masuda, 1957;Maley and Plaut, 1959;Plaut, 1960Plaut, , 1963 whose derivatives flavin mononucleotide (FMN) and flavin adenine dinucleotide (FAD) are universally distributed and are involved in an amazing variety of essential biological processes; for recent reviews, see Walsh and Wencewicz (2013) and Piano et al (2017).…”

Section: Introductionmentioning

confidence: 99%

Non-classical disproportionation revealed by photo-chemically induced dynamic nuclear polarization NMR

et al. 2021

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Abstract. Photo-chemically induced dynamic nuclear polarization (photo-CIDNP) was used to observe the light-induced disproportionation reaction of 6,7,8-trimethyllumazine starting out from its triplet state to generate a pair of radicals comprising a one-electron reduced and a one-electron oxidized species. Our evidence is based on the measurement of two marker proton hyperfine couplings, Aiso(H(6α)) and Aiso(H(8α)), which we correlated to predictions from density functional theory. The ratio of these two hyperfine couplings is reversed in the oxidized and the reduced radical species. Observation of the dismutation reaction is facilitated by the exceptional C–H acidity of the methyl group at position 7 of 6,7,8-trimethyllumazine and the slow proton exchange associated with it, which leads to NMR-distinguishable anionic (TML−) and neutral (TMLH) protonation forms.

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Naturally Occurring Lumazines

Cited by 8 publications

References 123 publications

Antibacterial and NF-κB Inhibitory Lumazine Peptides, Aspochalasin, γ-Butyrolactone Derivatives, and Cyclic Peptides from a Hawaiian Aspergillus flavipes

Antibacterial and NF-κB Inhibitory Lumazine Peptides, Aspochalasin, γ-Butyrolactone Derivatives, and Cyclic Peptides from a Hawaiian Aspergillus flavipes

Dilute-and-Shoot-Liquid Chromatography-Quadrupole Time of Flight-Mass Spectrometry for Pteridine Profiling in Human Urine and Its Association with Different Pathologies

Non-classical disproportionation revealed by photo-chemically induced dynamic nuclear polarization NMR

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