41019-50-5

Upstream product

• 57620-99-2 2-acetyllapachol 
• 84-79-7 Lapachol 

Downstream Products

• 15297-92-4 2,2-dimethyl-2H-benzo[g]chromene-5,10-dione 
• 15297-99-1 nor-lapachol 
• 15298-00-7 dihydroxyhydrolapachol 
• 84-79-7 Lapachol 
• 88-99-3 benzene-1,2-dicarboxylic acid 

Relevant academic research and scientific papers

Design of hybrid molecules as antimycobacterial compounds: Synthesis of isoniazid-naphthoquinone derivatives and their activity against susceptible and resistant strains of Mycobacterium tuberculosis

Isoniazid-naphthoquinone hybrids were synthesized and evaluated against a susceptible (H37Rv) strain and two isoniazid-resistant strains (INHR1 and INHR2) of Mycobacterium tuberculosis. The antimycobacterial activity of the derivatives was determined based on the resazurin microtiter assay and their cytotoxicity in adhered mouse monocyte macrophage J774.A1 cells (ATCC TIB-67). Of the twenty-two compounds evaluated against the three strains of M. tuberculosis, twenty-one presented some activity against the H37Rv and INHR1 (katG S315T) or INHR2 (inhA C(?5)T) strains. Compounds 1a, 2a, and 8a were effective against the INHR1 strain, and compounds 1a, 1b, 2a, 3a, 5a, 5b and 8a were effective against the INHR2 strain, with MICs in the range of 3.12–6.25 μg/mL. Compounds 1b and 5b were the most active against H37Rv, with MIC of 0.78 μg/mL. Based on the selectivity index, 1b and 5b can be considered safe as a drug candidate compounds. These results demonstrate that quinoidal compounds can be used as promising scaffolds for the development of new anti-TB drugs and hybrids with activity against M. tuberculosis-susceptible and INH-resistant strains.

Cyclometalated ruthenium complexes from naturally occurring quinones: studies on their photophysical features, computational details and trypanocidal activity

Phenazinic ligands and Ru(ii)-based complexes were synthesized from natural products lapachol and lawsone and evaluated against T. cruzi, the etiological agent of Chagas disease. These new ruthenium compounds could provide promising trypanocidal drugs. Besides synthesis and trypanocidal activity, this paper reports photophysical features and computational details of the compounds. The fluorescent trypanocidal substances are promising derivatives for further studies aiming to find molecules active against parasites associated with neglected diseases.

A macrolactone from benzo[a]phenazine with potent activity against Mycobacterium tuberculosis

We report here an alternative to the MCPBA or ozonolysis-based oxidation methods of quinoxaline-featuring compounds prepared from beta-lapachones. The use of peracetic acid allowed a simple preparation of the corresponding macrolactones by cleavage of the ring system. These lactones were evaluated for their antimycobacterial potential and compound 4 turned out to have an MIC of 0.62 μg per mL on Mycocabteriumtuberculosis H37Rv. These results justify further research into its value as a potential lead for an original treatment of tuberculosis.

Lawsone, Juglone, and β-Lapachone Derivatives with Enhanced Mitochondrial-Based Toxicity

Naphthoquinones are among the most active natural products obtained from plants and microorganisms. Naphthoquinones exert their biological activities through pleiotropic mechanisms that include reactivity against cell nucleophiles, generation of reactive oxygen species (ROS), and inhibition of proteins. Here, we report a mechanistic antiproliferative study performed in the yeast Saccharomyces cerevisiae for several derivatives of three important natural naphthoquinones: lawsone, juglone, and β-lapachone. We have found that (i) the free hydroxyl group of lawsone and juglone modulates toxicity; (ii) lawsone and juglone derivatives differ in their mechanisms of action, with ROS generation being more important for the former; and (iii) a subset of derivatives possess the capability to disrupt mitochondrial function, with β-lapachones being the most potent compounds in this respect. In addition, we have cross-compared yeast results with antibacterial and antitumor activities. We discuss the relationship between the mechanistic findings, the antiproliferative activities, and the physicochemical properties of the naphthoquinones.

Naphthoquinone-based chalcone hybrids and derivatives: Synthesis and potent activity against cancer cell lines

Novel naphthoquinone-based chalcones were prepared from the reaction between 3-bromo-nor-β-lapachone and amino-chalcones. Lapachone derivatives are also described here. All the substances were evaluated against cancer and normal cell lines and several compounds demonstrated potent antitumor activity. This journal is

Conversion of lapachol to lomatiol: Synthesis of novel naphthoquinone derivatives

Lapachol (1), a naphthoquinone isolated mostly from the plants of the bignoniaceae family has a broad spectrum of biological activities and as a consequence it has been the object of different chemical transformations. Lomatiol (3), another naturally occurring naphthoquinone having structural similarities to lapachol, has been obtained from chemical and microbial transformations of lapachol in very low yields. In the present study, an easy approach for the synthesis of lomatiol (3) from lapachol (1) has been developed using SeO2 oxidation in 90% yield. Lomatiol, under epoxidation conditions afforded novel furano- and pyrano-naphthoquinone derivatives, which are analogues of anticancer agents, 2-acetylfuronaphthoquinone and β-lapachone. Most of the structures were unambiguously confirmed by single crystal X-ray analysis.

A mechanistic study on the Hooker oxidation: Synthesis of novel indane carboxylic acid derivatives from lapachol

The Hooker oxidation is one of the most intriguing transformations wherein lapachol (1) is readily converted to norlapachol (2) in very good yield. This one-pot reaction involves a very intricate mechanism in which the alkyl side chain of lapachol is shortened by one carbon unit. Previous studies have unequivocally established the involvement of an indane carboxylic acid derivative 3, as a key intermediate (Hooker intermediate), and its simultaneous conversion to norlapachol (2) via the oxidative cleavage of vicinol diol and subsequent intramolecular aldol reaction of the resulting keto acid. However, the formation of the key Hooker intermediate 3 from lapachol (1) remains ambiguous. The present study has thrown some light on the formation of the key intermediate 3 from lapachol (1) via benzilic acid rearrangement of the corresponding labile o-diquinone intermediate 8 derived from lapachol. The involvement of o-diquinone intermediate 8 in the Hooker oxidation has been further established by trapping of this labile intermediate as the corresponding phenazine derivative 9. The involvement of benzilic acid rearrangement as a key step in the Hooker oxidation is further shown with a variety of o-quinones prepared from lapachol (1). The Royal Society of Chemistry 2013.

Cytotoxicity of lapachol, β-lapachone and related synthetic 1,4-naphthoquinones against oesophageal cancer cells

Naphthoquinones have been found to have a wide range of biological activities, including cytotoxicity to cancer cells. The secondary metabolites lapachol, α- and β-lapachone and a series of 25 related synthetic 1,4-naphthoquinones were screened against the oesophageal cancer cell line (WHCO1). Most of the compounds exhibited enhanced cytotoxicity (IC50 1.6-11.7 μM) compared to the current drug of choice cisplatin (IC 50 = 16.5 μM). This study also established that the two new synthetic halogenated compounds 12a and 16a (IC50 = 3.0 and 7.3 μM) and the previously reported compound 11a (IC50 = 3.9 μM), were non-toxic to NIH3T3 normal fibroblast cells. Cell death of oesophageal cancer cells by processes involving PARP cleavage caused by 11a was shown to be associated with elevated c-Jun levels, suggesting a role for this pathway in the mechanism of action of this cohort of naphthoquinone compounds.

Synthesis and pharmacophore modeling of naphthoquinone derivatives with cytotoxic activity in human promyelocytic leukemia HL-60 cell line

Catalyst/HypoGen pharmacophore modeling approach and three-dimensional quantitative structure-activity relationship (3D-QSAR)/comparative molecular similarity indices analysis (CoMSIA) methods have been successfully applied to explain the cytotoxic activity of a set of 51 natural and synthesized naphthoquinone derivatives tested in human promyelocytic leukemia HL-60 cell line. The computational models have facilitated the identification of structural elements of the ligands that are key for antitumoral properties. The four most salient features of the highly active β-cycled-pyran-1,2-naphthoquinones [0.1 μM 50 0.6 μM] are the hydrogen-bond interactions of the carbonyl groups at C-1 (HBA1) and C-2 (HBA2), the hydrogen-bond interaction of the oxygen atom of the pyran ring (HBA3), and the interaction of methyl groups (HYD) at the pyran ring with a hydrophobic area at the receptor. The moderately active 1,4-naphthoquinone derivatives accurately fulfill only three of these features. The results of our study provide a valuable tool in designing new and more potent cytotoxic analogues.

Radermachera xylocarpa: The highly efficient source of lapachol and synthesis of its derivatives

Isolation and characterization of the major chemical constituents from the stem bark of Radermachera xylocarpa. Chloroform extract of the powdered stem bark contains mainly two components: one is lapachol (91.2%) and second is α-lapachone (5.0%), which are reported herewith first time from this plant, in good quantity and purity.