Highly Efficient Synthesis and Structure–Activity Relationships of a Small Library of Substituted 1,4‐Naphthoquinones

Abstract

A platform of highly efficient synthetic methodologies has been established to access a focused library of substituted 1,4‐naphthoquinones derivatives functionalized with a diversity of amino/hydroxy/alkyl groups. Furthermore, the structure–activity relationship deduced from antiproliferative activities and toxicities of this 1,4‐naphthoquinone library and intracellular reactive oxygen species (ROS) level detections might warrant future potential of plumbagin (2) and compound 13 as promising basic structures to develop novel anti‐cancer agents.

Chemical, Bioactivity, and Biosynthetic Screening of Epiphytic Fungus Zasmidium pseudotsugae

“…Based on the HMBC correlations, δ H 7.24 (H-7,7 ) and 6.71 ppm (H-2,2 ) with δ C 128.3 ppm (C-8a,8a') as well as δ H 12.49 (OH-5,5 ), 7.31 (H-6,6 ) and 6.92 ppm (H-3,3 ) with δ C 115.5 ppm (C-4a,4a'), the 8,8 -linkage was suggested. Previous work by H. Laatsch showed differences in the UV absorption maxima for synthetic 8,8 -bijuglone (437 nm) versus 6,6 -bijuglone (445 nm) as well as a larger downfield shifts of the OH-signal from monomer (δ H 10.83) to the dimer of ∆δ H of 0.7 ppm for 8,8 -linkage as observed here [26,27]. The 8,8 -dimeric naphthoquinone represents a unique case where the proton and carbon environments are chemically and magnetically equivalent.…”

Advances in the Synthesis of Methylated Products through Indirect Approaches

“…To explore a much more feasible procedure to construct the methyl moiety in the product 53 , Sun and co‐workers prepared the Mannich base 52 from the starting material 51 (Scheme ) . The debenzylation of compound 52 was achieved initially with Pd‐C in the presence of H 2 in 50% yield.…”

Novel one-pot synthesis of a library of 2-aryloxy-1,4-naphthoquinone derivatives. Determination of antifungal and antibacterial activity

“…Both lapachol and lawsone exhibit antimalarial, anti-cancer, antitrypanosomal, antifungal and antibacterial properties that have been used as natural remedies in indigenous communities, 16,17 and both structures can be modified for the development of new drugs that will potentially present selective and efficient mechanisms against malaria, cancer, bacteria and fungi. 8,18–23 Fieser and co-workers, in work that extended over a quarter century, determined the physical and chemical properties of lapachol and lawsone and some synthetic derivatives, in order to evaluate their activity against Plasmodium species. 24–31 Based on Fieser's seminal work, a series of metal complexes 18,32,33 and C2 and/or C3 naphthoquinone substituted derivatives, such as alkyl, 34,35 nitrogen, 36–43 sulfur, 39,41,44–48 and oxygen-containing 21,22,42,49–51 molecules have been proposed as potential antitumoral, antibacterial, antiparasitical, antiviral and antifungal agents.…”