481-42-5

Usage

Uses

Used in Pharmaceutical Applications:
PLUMBAGIN is used as an antibacterial, antifungal, and tuberculostatic agent for its potent antimicrobial properties, making it effective against various bacterial, fungal, and tuberculosis-causing pathogens.
Used in Pest Control:
PLUMBAGIN is used as an antifeedant for worms, preventing them from feeding on crops and reducing the damage caused by these pests.
Used in Cancer Research:
PLUMBAGIN is used as a reactive oxygen species (ROS) agent for inducing cytotoxicity in mouse embryonic fibroblasts, contributing to the study of cancer cell behavior and the development of potential cancer treatments.
Used in Yeast Studies:
PLUMBAGIN is used as an oxidative stress inducer to generate superoxide anion in Saccharomyces cerevisiae, aiding in the understanding of oxidative stress response mechanisms in yeast cells.
Used in Analytical Chemistry:
PLUMBAGIN is used as a reference standard in thin-layer chromatography and spectrophotometric analysis for the quantification of plumbagin in Plumbago auriculate samples, ensuring accurate measurement and analysis of this bioactive compound.
Used in Antioxidant Research:
PLUMBAGIN is used to activate signaling through Nrf2 and the antioxidant response element, inducing the expression of Nrf2 target genes, such as NQO1 and heme oxygenase-1 in cultured neuronal cells. This application helps in studying the protective mechanisms against peroxide stress or deprivation of glucose or oxygen.
Used in the Study of NADPH Oxidase Inhibition:
PLUMBAGIN is used to inhibit NADPH oxidase 4 in a timeand dose-dependent manner, providing insights into the regulation of this enzyme and its role in various cellular processes.

Biochem/physiol Actions

Plumbagin exhibits various pharmacological activities including antimicrobial, anticancer, anti-atherosclerotic, antidiabetic, anti-inflammatory, hypolipidemic, and neuroprotective activities. It inhibits the signal transducer and activator of transcription 3 (STAT3) signaling and halts the proliferation of esophageal squamous cell carcinoma (ESCC). Plumbagin elicits protective antioxidative functionality in 4-nitroquinoline-N-oxide (NQNO) induced stress in lymphoma. Plumbagin in a nanoemulsion formulation has antiproliferative effect towards prostate cancer.

in vitro

plumbagin exhibited effective cell growth inhibition via inducing cancer cells to undergo g2/m phase arrest and apoptosis. blockade of cell cycle was associated with increased levels of p21 and reduced amounts of cdc2, cdc25c and cyclinb1. plumbagin treatment also found to enhance the levels of inactivated phosphorylated cdc2 and cdc25c. blockade of p53 activity partially decreased plumbagin-induced apoptosis and g2/m arrest, indicating it might be operated by p53-dependent and independent pathway [1].

in vivo

to determine whether plumbagin inhibited the in vivo tumor growth, a549 cells were injected into nude mice. tumor growth inhibition was most evident in mice treated with plumbagin at 2 mg/kg/day, where around 80% reductions in tumor size were observed, in contrast with mice treated with the vehicle. no sign of toxicity was observed in plumbagin-treated mice as judged by monitoring body weight [1].

IC 50

11.69 μm for a549 cells

Purification Methods

It crystallises in yellow needles from aqueous EtOH. It is soluble in organic solvents, it is steam volatile and it sublimes on heating in a vacuum. [Fieser & Dunn J Am Chem Soc 58 572 1936, Beilstein 8 III 2576, 8 IV 2376.]

references

[1] hsu yl,cho cy,kuo pl,huang yt,lin cc. plumbagin (5-hydroxy-2-methyl-1,4-naphthoquinone) induces apoptosis and cell cycle arrest in a549 cells through p53 accumulation via c-jun nh2-terminal kinase-mediated phosphorylation at serine 15 in vitro and in vivo. j pharmacol exp ther.2006 aug;318(2):484-94.

InChI:InChI=1/C11H8O3/c1-6-5-9(13)10-7(11(6)14)3-2-4-8(10)12/h2-5,12H,1H3

Synthetic route

2-bromo-5-hydroxy-[1,4]naphthoquinone (69008-03-3) + tetramethylstannane (594-27-4) → 5-hydroxy-2-methyl-1,4-naphthoquinone (481-42-5)

Conditions	Yield
tetrakis(triphenylphosphine) palladium(0); copper(I) bromide In 1,4-dioxane for 15h; Heating;	100%
tetrakis(triphenylphosphine) palladium(0); copper(I) bromide In 1,4-dioxane for 15h; Heating; Yield given;

6-methyl-5,8-dioxo-5,8-dihydronaphthalen-1-yl acetate (116752-29-5) → 5-hydroxy-2-methyl-1,4-naphthoquinone (481-42-5)

Conditions	Yield
With hydrogenchloride In methanol at 50℃; for 1h;	100%

5-methoxymethoxy-2-methyl-1,4-naphthoquinone (106914-49-2) → 5-hydroxy-2-methyl-1,4-naphthoquinone (481-42-5)

Conditions	Yield
With toluene-4-sulfonic acid In neat (no solvent, solid phase) at 20℃; for 0.583333h; Green chemistry;	97%
With hydrogenchloride In methanol for 0.0833333h; Heating;	95%

2,2,5-trimethylnaphtho-[1,8-de]-1,3-dioxin-6-ol → 5-hydroxy-2-methyl-1,4-naphthoquinone (481-42-5)

Conditions	Yield
With cerium(IV) ammonium sulphate In water; acetonitrile for 0.25h; Cooling with ice;	95%
With ammonium cerous sulfate In water; acetonitrile at 0℃; for 0.25h;	95%

2-methyl-5-methoxy-1,4-naphthoquinone (22266-99-5) → 5-hydroxy-2-methyl-1,4-naphthoquinone (481-42-5)

Conditions	Yield
With aluminium trichloride	90%
With aluminium trichloride In dichloromethane 1.) 1 h, room temp., 2.) 15 min, water;	90%
With aluminium trichloride In dichloromethane at 20℃; for 2h;	75%

diomuscinone → 5-hydroxy-2-methyl-1,4-naphthoquinone (481-42-5)

Conditions	Yield
With sodium hydride In tetrahydrofuran for 15h; Ambient temperature;	82%

2-Methyl-1,5-naphthalindiol-5-acetat (116752-27-3) → 5-hydroxy-2-methyl-1,4-naphthoquinone (481-42-5)

Conditions	Yield
With oxygen; methylene blue In methanol at 20℃; for 4h; Irradiation;	69%
Multi-step reaction with 2 steps 1: 74 percent / aq. ON(SO3K)2, KH2PO4 / methanol / 2 h 2: 100 percent / conc. HCl / methanol / 1 h / 50 °C View Scheme

menadione (58-27-5) → 5-hydroxy-2-methyl-1,4-naphthoquinone (481-42-5)

Conditions	Yield
With [ruthenium(II)(η6-1-methyl-4-isopropyl-benzene)(chloride)(μ-chloride)]2; trifluoroacetic acid; trifluoroacetic anhydride; bis-[(trifluoroacetoxy)iodo]benzene at 80℃; for 12h; Sealed tube; chemoselective reaction;	61%
With ammonium peroxydisulfate; sulfuric acid

5-acetyloxy-3-bromo-2-methyl-1,4-naphthoquinone (101927-36-0) + Bu3SnH → 5-hydroxy-2-methyl-1,4-naphthoquinone (481-42-5)

Conditions	Yield
at 145℃; for 12h;	60%

1,8-Dihydroxy-3-methylnaphthalin (1130-61-6) → 5-hydroxy-2-methyl-1,4-naphthoquinone (481-42-5) + 7-methyljuglone (14787-38-3)

Conditions	Yield
With salcomine; oxygen In N,N-dimethyl-formamide at 20℃; for 1h; Inert atmosphere;	A 51% B 30%

2-bromo-5-hydroxy-[1,4]naphthoquinone (69008-03-3) + <2,6-dimethoxy-4-methylphenyl>trimethylstannane (126421-39-4) → 5-hydroxy-2-methyl-1,4-naphthoquinone (481-42-5) + 2-(2,6-Dimethoxy-4-methylphenyl)-5-hydroxy-1,4-naphthoquinone (137057-03-5)

Conditions	Yield
tetrakis(triphenylphosphine) palladium(0) In 1,4-dioxane for 3h; Heating;	A 6% B 46%

2-bromo-5-hydroxy-[1,4]naphthoquinone (69008-03-3) + lithium dimethylcuprate (15681-48-8) → 5-hydroxy-2-methyl-1,4-naphthoquinone (481-42-5)

Conditions	Yield
In tetrahydrofuran at -78℃;	42%

1-methoxy-2-methyl-4,5-naphthylene diacetate (848141-72-0) → 5-hydroxy-2-methyl-1,4-naphthoquinone (481-42-5) + 8,8'-dihydroxy-3,3'-dimethyl[2,2']binaphthalenyl-1,4,1',4'-tetraone (34341-27-0)

Conditions	Yield
Stage #1: 1-methoxy-2-methyl-4,5-naphthylene diacetate With potassium hydroxide In methanol for 0.5h; Heating; Stage #2: With lead dioxide In chloroform for 0.5h; Heating;	A 23% B 0.3%

1,5-Dihydroxy-2-methylnaphthalin (79786-99-5) → 5-hydroxy-2-methyl-1,4-naphthoquinone (481-42-5) + 5-hydroxy-6-methyl-1,4-naphthoquinone (60011-38-3)

Conditions	Yield
With potassium dihydrogenphosphate; potassium nitrososulfonate In methanol for 2h;	A n/a B 15%
With potassium dihydrogenphosphate; potassium nitrososulfonate In methanol for 2h;	A n/a B 15%

(3R,4R)-4,8-dihydroxy-3-methyl-3,4-dihydro-1(2H)-naphthalenone (39626-94-3, 72058-77-6, 92694-13-8, 39626-91-0) → 5-hydroxy-2-methyl-1,4-naphthoquinone (481-42-5) + 1,2(3)-tetrahydro-3,3'-biplumbagin

Conditions	Yield
With 2,3-dicyano-5,6-dichloro-p-benzoquinone In 1,4-dioxane for 12h; Heating;	A n/a B 0.005%
With 2,3-dicyano-5,6-dichloro-p-benzoquinone In 1,4-dioxane for 12h; Heating;

ethanol (64-17-5) + 5-hydroxy-2-methyl-[1,4]naphthoquinone; compound with hydroquinone → 5-hydroxy-2-methyl-1,4-naphthoquinone (481-42-5) + hydroquinone (123-31-9)

ethanol (64-17-5) + 5-hydroxy-2-methyl-[1,4]naphthoquinone; compound with naphthol-(1) → α-naphthol (90-15-3) + 5-hydroxy-2-methyl-1,4-naphthoquinone (481-42-5)

2-methyl-1,4,5-naphthalenetriol (58274-93-4) → 5-hydroxy-2-methyl-1,4-naphthoquinone (481-42-5)

Conditions	Yield
With dihydrogen peroxide

5-hydroxy-2-methyl-[1,4]naphthoquinone; compound with hydroquinone + acetic acid (64-19-7) → 5-hydroxy-2-methyl-1,4-naphthoquinone (481-42-5) + hydroquinone (123-31-9)

5-hydroxy-2-methyl-[1,4]naphthoquinone; compound with naphthol-(1) + acetic acid (64-19-7) → α-naphthol (90-15-3) + 5-hydroxy-2-methyl-1,4-naphthoquinone (481-42-5)

(3R,4R)-4,8-dihydroxy-3-methyl-3,4-dihydro-1(2H)-naphthalenone (39626-94-3, 72058-77-6, 92694-13-8, 39626-91-0) → 5-hydroxy-2-methyl-1,4-naphthoquinone (481-42-5)

Conditions	Yield
With 2,3-dicyano-5,6-dichloro-p-benzoquinone In 1,4-dioxane for 18h; Heating;	22 mg
With pyridine; chromium(VI) oxide In chloroform for 24h;

plumbazeylanone (94410-15-8) → 5-hydroxy-2-methyl-1,4-naphthoquinone (481-42-5) + methylene-3,3'-diplumbagin (58275-00-6)

Conditions	Yield
at 240℃; under 4.5 Torr; for 0.0833333h;

(4aR,5R,8aR)-4a-Chloro-2-methyl-5-trimethylsilanyloxy-4a,5,8,8a-tetrahydro-[1,4]naphthoquinone → 5-hydroxy-2-methyl-1,4-naphthoquinone (481-42-5)

Conditions	Yield
With chromium(VI) oxide; acetic acid for 1.5h; Heating; Yield given;

5-hydroxynaphtho-1,4-quinone (481-39-0) + acetic acid (64-19-7) → 5-hydroxy-2-methyl-1,4-naphthoquinone (481-42-5) + isoplumbagin (14777-17-4) + 2,3-dimethyl-5-hydroxy-1,4-naphthoquinone (80596-51-6)

Conditions	Yield
With ammonium peroxydisulfate; silver nitrate 1.) Acetonitril, 80 deg C, 2.) H2O, Rueckfluss, 2 h; Multistep reaction;

1,4,5-Triacetoxy-8-chlor-2-methylnaphthalin (89475-06-9) → 5-hydroxy-2-methyl-1,4-naphthoquinone (481-42-5)

Conditions	Yield
Yield given. Multistep reaction;

2-methyl-5-amino-1,4-naphthoquinone (116415-35-1) → 5-hydroxy-2-methyl-1,4-naphthoquinone (481-42-5)

Conditions	Yield
With nitrosylsulfuric acid; sulfuric acid; water 1.) 4 h, 2.) 2 h, reflux; Yield given. Multistep reaction;
Multi-step reaction with 2 steps 1: 48 percent / NaNO2 / 3 h / Heating 2: 1.) ON(SO3K)2, 0.167 M K2HPO4, 2.) H2O / 1.) 4 h, 2.) 2 h, reflux View Scheme

5-Acetamido-2-methyl-1,4-naphthochinon (116415-36-2) → 5-hydroxy-2-methyl-1,4-naphthoquinone (481-42-5)

Conditions	Yield
With dipotassium hydrogenphosphate; potassium nitrososulfonate; water 1.) 4 h, 2.) 2 h, reflux; Yield given. Multistep reaction;

(S)-4,8-Dihydroxy-3-methyl-3,4-dihydro-2H-naphthalen-1-one → 5-hydroxy-2-methyl-1,4-naphthoquinone (481-42-5)

Conditions	Yield
With 2,3-dicyano-5,6-dichloro-p-benzoquinone In 1,4-dioxane for 8h; Heating;

(-)-5-hydroxy-2-methyl-2,3-dihydro-1,4-naphthoquinone → 5-hydroxy-2-methyl-1,4-naphthoquinone (481-42-5)

Conditions	Yield
With chromium(VI) oxide; sulfuric acid In sodium hydroxide for 0.0333333h;	12 mg

rel-(10S,1S,4R,4aS,9aR)-5,10-Dihydroxy-5,10-di-O-isopropylidene-1,4-methano-9a-methyl-9-oxo-1,4,4a,9,9a,10-hexahydroanthracene → 5-hydroxy-2-methyl-1,4-naphthoquinone (481-42-5)

Conditions	Yield
With hydrogenchloride; iron(III) chloride 1.) toluene, 270 deg C, 30 min, 2.) MeOH, 3 h; Yield given. Multistep reaction;

5-hydroxy-2-methyl-1,4-naphthoquinone (481-42-5) + methyl iodide (74-88-4) → 2-methyl-5-methoxy-1,4-naphthoquinone (22266-99-5)

Conditions	Yield
With silver(l) oxide In dichloromethane at 20℃; for 48h; Inert atmosphere;	99%
With silver(l) oxide	94%
With silver(l) oxide In chloroform Ambient temperature;	93%

5-hydroxy-2-methyl-1,4-naphthoquinone (481-42-5) + n-hexadecanoyl chloride (112-67-4) → plumbagin palmitate

Conditions	Yield
Stage #1: 5-hydroxy-2-methyl-1,4-naphthoquinone With triethylamine In diethyl ether at 20℃; for 0.5h; Stage #2: n-hexadecanoyl chloride In diethyl ether at 20℃; for 1h;	99%

n-dodecanoyl chloride (112-16-3) + 5-hydroxy-2-methyl-1,4-naphthoquinone (481-42-5) → 5-dodecanoyloxy-2-methyl-1,4-naphthoquinone

Conditions	Yield
Stage #1: 5-hydroxy-2-methyl-1,4-naphthoquinone With triethylamine In diethyl ether at 20℃; for 0.5h; Stage #2: n-dodecanoyl chloride In diethyl ether at 20℃; for 1h;	98%

5-hydroxy-2-methyl-1,4-naphthoquinone (481-42-5) + tetradecanoyl chloride (112-64-1) → plumbagin myristate

Conditions	Yield
Stage #1: 5-hydroxy-2-methyl-1,4-naphthoquinone With triethylamine In diethyl ether at 20℃; for 0.5h; Stage #2: tetradecanoyl chloride In diethyl ether at 20℃; for 1h;	98%

5-hydroxy-2-methyl-1,4-naphthoquinone (481-42-5) + Stearoyl chloride (112-76-5) → 5-octadecanoyloxy-2-methyl-1,4-naphthoquinone

Conditions	Yield
Stage #1: 5-hydroxy-2-methyl-1,4-naphthoquinone With triethylamine In diethyl ether at 20℃; for 0.5h; Stage #2: Stearoyl chloride In diethyl ether at 20℃; for 1h;	96%

(Z)-9-octadecenoyl chloride (112-77-6) + 5-hydroxy-2-methyl-1,4-naphthoquinone (481-42-5) → 5-{(Z)-octadecenylalkanoyloxy}-2-methyl-1,4-naphthoquinone

Conditions	Yield
Stage #1: 5-hydroxy-2-methyl-1,4-naphthoquinone With triethylamine In diethyl ether at 20℃; for 0.5h; Stage #2: (Z)-9-octadecenoyl chloride In diethyl ether at 20℃; for 1h;	96%

5-hydroxy-2-methyl-1,4-naphthoquinone (481-42-5) + acetic anhydride (108-24-7) → 6-methyl-5,8-dioxo-5,8-dihydronaphthalen-1-yl acetate (116752-29-5)

Conditions	Yield
With pyridine for 2h; Ambient temperature;	94%
With pyridine at 20℃; for 10h;	93%
With pyridine at 20℃; for 4h;	90%
With triethylamine In diethyl ether at 20℃; for 0.5h;

5-hydroxy-2-methyl-1,4-naphthoquinone (481-42-5) + chloromethyl methyl ether (107-30-2) → 5-methoxymethoxy-2-methyl-1,4-naphthoquinone (106914-49-2)

Conditions	Yield
Stage #1: 5-hydroxy-2-methyl-1,4-naphthoquinone With sodium hydride In N,N-dimethyl-formamide; paraffin oil at 0℃; for 0.0833333h; Stage #2: chloromethyl methyl ether In 1,2-dimethoxyethane; paraffin oil at 0℃; for 1.5h;	94%
With potassium carbonate In acetone

1-bromo-4-(2-vinylbuta-1,3-dienyl)benzene (906351-28-8) + 5-hydroxy-2-methyl-1,4-naphthoquinone (481-42-5) → (4aRS,9aSR)-1-(4-bromophenyl)-5-hydroxy-9a-methyl-2-vinyl-1,4,4a,9a-tetrahydroanthracene-9,10-dione

Conditions	Yield
With boron trifluoride diethyl etherate In dichloromethane at -35℃; Diels-Alder Cycloaddition; Inert atmosphere;	92%
With boron trifluoride diethyl etherate In dichloromethane at -30℃; Diels-Alder reaction;

5-hydroxy-2-methyl-1,4-naphthoquinone (481-42-5) + propionic acid (802294-64-0) → 5-O-propionoyl-2-methyl-1,4-naphthoquinone (1238220-30-8)

Conditions	Yield
With dmap; 2-methyl-6-nitrobenzoic anhydride; triethylamine In dichloromethane at 20℃; for 2h;	89%

5-hydroxy-2-methyl-1,4-naphthoquinone (481-42-5) + N-sulfinyl-4-methylaniline (15795-42-3) → 5-hydroxy-2-methyl-4-(4-methylphenyl)imino-1,4-dihydronaphthalen-1-one

Conditions	Yield
In benzene for 72h; Ambient temperature;	87%

5-hydroxy-2-methyl-1,4-naphthoquinone (481-42-5) + 2,2,2-Trichloroethyl chloroformate (17341-93-4) → O-trichloroethoxycarbonyl-plumbagone

Conditions	Yield
Stage #1: 5-hydroxy-2-methyl-1,4-naphthoquinone With pyridine In dichloromethane at 0℃; Inert atmosphere; Stage #2: 2,2,2-Trichloroethyl chloroformate In dichloromethane	87%

5-hydroxy-2-methyl-1,4-naphthoquinone (481-42-5) + ethyl iodide (75-03-6) → plumbagin ethyl ether

Conditions	Yield
Stage #1: 5-hydroxy-2-methyl-1,4-naphthoquinone With potassium carbonate In acetone at 20℃; for 0.0833333h; Stage #2: ethyl iodide In acetone at 80℃; for 1h;	87%

lauric acid (143-07-7) + 5-hydroxy-2-methyl-1,4-naphthoquinone (481-42-5) → 5-dodecanoyloxy-2-methyl-1,4-naphthoquinone

Conditions	Yield
With dmap; 2-methyl-6-nitrobenzoic anhydride; triethylamine In dichloromethane at 20℃;	86%

5-hydroxy-2-methyl-1,4-naphthoquinone (481-42-5) → 5-hydroxy-6-iodo-2-methyl-1,4-naphthoquinone

Conditions	Yield
With N-iodo-succinimide; dichloro(pentamethylcyclopentadienyl)rhodium (III) dimer; copper diacetate; silver(I) triflimide In dichloromethane at 45℃; for 2h; Inert atmosphere; Sealed tube; Microwave irradiation;	85%

copper(II) nitrate trihydrate + 5-hydroxy-2-methyl-1,4-naphthoquinone (481-42-5) + 4'-phenyl-2,2':6',2-terpyridine (58345-97-4) → [Cu(4'‐phenyl‐2,2':6',2''‐terpyridine)(plum)]NO3

Conditions	Yield
Stage #1: copper(II) nitrate trihydrate; 4'-phenyl-2,2':6',2-terpyridine In methanol; chloroform at 20℃; for 1h; Stage #2: 5-hydroxy-2-methyl-1,4-naphthoquinone With triethylamine In methanol; chloroform for 0.5h; Cooling with ice;	84%

1,10-Phenanthroline (66-71-7) + 5-hydroxy-2-methyl-1,4-naphthoquinone (481-42-5) + copper(I) bromide (7787-70-4) → C23H15BrCuN2O3*CH4O

Conditions	Yield
With sodium methylate In methanol at 20℃; for 2.5h; Reflux;	81%

5-hydroxy-2-methyl-1,4-naphthoquinone (481-42-5) + 2-bromoethyl phenyl selenide (50630-23-4) → C19H16O3Se

Conditions	Yield
With silver nitrate In acetonitrile at 20℃; for 1h;	81%

5-hydroxy-2-methyl-1,4-naphthoquinone (481-42-5) + (5Z,8Z,11Z,14Z,17Z)-eicosa-5,8,11,14,17-pentaenoyl chloride (98770-65-1) → 5-eicosapentaenoyloxy-2-methyl-1,4-naphthoquinone

Conditions	Yield
With pyridine; dmap at 20℃; for 4h; Inert atmosphere;	80%

5-hydroxy-2-methyl-1,4-naphthoquinone (481-42-5) + 4-chloro-3-trifluoromethyl-aniline (320-51-4) → 3-(4-chloro-3-trifluoromethyl-phenylamino)-5-hydroxy-2-methyl-[1,4]naphthoquinone

Conditions	Yield
With trifluoroacetic acid In methanol for 6h; Reflux;	80%

5-hydroxy-2-methyl-1,4-naphthoquinone (481-42-5) + 3-chloro-4-trifluoromethoxy-aniline (64628-73-5) → 3-(3-chloro-4-trifluoromethoxy-phenylamino)-5-hydroxy-2-methyl-[1,4]naphthoquinone

Conditions	Yield
With trifluoroacetic acid In methanol for 6h; Reflux;	80%

5-hydroxy-2-methyl-1,4-naphthoquinone (481-42-5) + dimethyltin(IV) diisopropoxide (26900-62-9) → (CH3)2Sn(C10H4O2(O)CH3)2

Conditions	Yield
In benzene byproducts: isopropanol; addn. of ligand to tin compd. soln. (ratio 2/1); refluxing; azeotropically fractionating, 3-5h; evapn.; crystn. (benzene or benzene/hexane 1/1); elem. anal.;	79%

bis(isopropoxy)diphenyltin(IV) + 5-hydroxy-2-methyl-1,4-naphthoquinone (481-42-5) → (C6H5)2Sn(C10H4O2(O)CH3)2

Conditions	Yield
In benzene byproducts: isopropanol; addn. of ligand to tin compd. soln. (ratio 2/1); refluxing; azeotropically fractionating, 3-5h; evapn.; crystn. (benzene or benzene/hexane 1/1); elem. anal.;	79%

1,10-Phenanthroline (66-71-7) + copper(II) nitrate trihydrate + 5-hydroxy-2-methyl-1,4-naphthoquinone (481-42-5) → C23H15CuN2O3(1+)*NO3(1-)*0.25H2O

Conditions	Yield
With sodium methylate In methanol at 20℃; for 2.5h; Reflux;	79%

Upstream product

• 64-17-5 ethanol 
• 58-27-5 menadione 
• 58274-93-4 2-methyl-1,4,5-naphthalenetriol 
• 64-19-7 acetic acid 
• 69008-03-3 2-bromo-5-hydroxy-[1,4]naphthoquinone 
• 15681-48-8 lithium dimethylcuprate 
• 594-27-4 tetramethylstannane 
• 126421-39-4 <2,6-dimethoxy-4-methylphenyl>trimethylstannane 
• 22266-99-5 2-methyl-5-methoxy-1,4-naphthoquinone 
• 116752-29-5 6-methyl-5,8-dioxo-5,8-dihydronaphthalen-1-yl acetate 
• 39626-94-3 (3R,4R)-4,8-dihydroxy-3-methyl-3,4-dihydro-1(2H)-naphthalenone 
• 94410-15-8 plumbazeylanone 
• 481-39-0 5-hydroxynaphtho-1,4-quinone 
• 89475-06-9 1,4,5-Triacetoxy-8-chlor-2-methylnaphthalin 

Downstream Products

• 21890-57-3 5-hydroxy-2-methyl-3-chloro-1,4-naphthoquinone 
• 57093-07-9 3,6-dichloro-5-hydroxy-2-methyl-[1,4]naphthoquinone 
• 22266-99-5 2-methyl-5-methoxy-1,4-naphthoquinone 
• 14554-09-7 5,8-dihydroxy-2-methyl-[1,4]naphthoquinone 
• 22273-47-8 5,6-dihydroxy-2-methyl-1,4-naphthoquinone 
• 188675-38-9 2-methyl-5-hydroxy-2,3-epoxy-2,3-dihydro-1,4-naphthoquinone 
• 222738-47-8 5-tert-butyldiphenylsilyloxy-2-methyl-1,4-naphthoquinone 
• 601-97-8 3-hydroxyphthalic acid 
• 1189394-39-5 3-(4-(tert-butyl)benzyl)-5-hydroxy-2-methylnaphthalene-1,4-dione 
• 1189394-82-8 3-(4-bromobenzoyl)-5-hydroxy-2-methylnaphthalene-1,4-dione 
• 1189394-37-3 3-(4-bromobenzyl)-5-hydroxy-2-methylnaphthalene-1,4-dione 

Relevant academic research and scientific papers

EPI-ISOSHINANOLONE FROM PLUMBAGO SCANDENS

Epi-isoshinanolone, a diastereomer of isoshinanolone, has been isolated from Plumbago scandens and characterized with the aid of NMR spectroscopy.Key Word Index - Plumbago scandens; Plumbaginaceae; epi-isoshinanolone; plumbagin; 13C NMR.

Axially Chiral Dimeric Naphthalene and Naphthoquinone Metabolites, from Root Cultures of the West African Liana Triphyophyllum peltatum

Root cultures of the West African liana Triphyophyllum peltatum were initiated from stem explants of in vitro cultivated shoots. From these organ cultures, three new binaphthalenes, one binaphthoquinone, and two (bi)naphthalene glucosides were isolated, with substitution patterns related to those of the naphthylisoquinoline alkaloids, which are the normal main metabolites of T. peltatum. The structures of the diglucoside dioncoquinoside A (1) and of the axially chiral biaryls triphyoquinols A1 (3), A2 (4), and B (5), triphyoquinoside A (6), and triphyoquinone A (7) were elucidated by spectroscopic analysis (HRESIMS, 1D and 2D NMR) and by application of electronic circular dichroism (ECD) spectroscopy in combination with the exciton chirality method and quantum-chemical ECD calculations. The root cultures likewise produced the known alkaloids dioncophylline A (8), 5′-O-demethyldioncophylline A (9), dioncopeltine A (10), habropetaline A (11), and 5′-O-methyldioncophylline D (12a/b), the naphthalene glucoside plumbaside A (2), and the naphthoquinones plumbagin (13), droserone (14), and 8-hydroxydroserone (15).

QUINONOID AND OTHER CONSTITUENTS OF ARISTEA ECKLONII

Aristea ecklonii; Iridaceae; quinones; plumbagin; biplumbagin; neoisoshinanolone; sterols.Plumbagin, 3,3'-biplumbagin, 8,8'-biplumbagin, neoisoshinanolone and sitosterol were isolated from the leaves and rhizomes of Aristea ecklonii.The rhizomes also contained α-spinasterol.This is the first report of plumbagin, previously found in several dicotyledonous families, in a monocotyledon.

NAPHTHOQUINONES AND TRITERPENES FROM SOME ASIAN DIOSPYROS SPECIES

Investigation of the stem bark, wood and/or fruit of nine Asian Diospyros spp. (Ebenaceae) has revealed a range ot triterpenes and naphthoquinones typical of the genus.In addition to lupeol, betulin and betulinic acid, which were present in all samples, seven other triterpenes were isolated and identified.Six of the nine species also yielded naphthoquinones.In two species these were based on 2-methyljuglone (plumbagin) and in the other four on 7-methyljuglone.Key Word Index -- Diospyros spp; Ebenaceae; simple and dimeric naphthoquinones; triterpenes; oleanane-type; ursane-type.

ISOLATION AND STRUCTURES OF DIOMUSCINONE AND DIOMUSCIPULONE FROM DIONAEA MUSCIPULA

From the fresh leaves and roots of Dionaea muscipula, two new substances (diomuscinone and diomuscipulone) have been isolated together with the known naphthoquinone plumbagin.The structures of the new compounds have been elucidated on the basis of their spectral data coupled with some chemical evidence. - Key Word Index: Dionaea muscipula; Droseraceae; phenolic compounds; diomuscinone; diomuscipulone.

1,4-Naphthoquinones, XXIV: On the dehalogenation of 2-/3-halogen-1,4-naphthoquinone derivatives

Bu3SnH is an effective reagent for the debromination of 2-bromonaphthoquinones but elimination of chlorine with 1c, e.g., only proceeds at 30%. With Et3SiH dechlorination does not occur at all. Instead, with the 5-acetoxy derivatives 1a/1d as starting materials the cyclic acetales 3a-c are formed as selectively protected juglone derivatives. The bromo derivative 3a is obtained only at temp. 10° and even at room temp. Br-Elimination occurs with low yield of 3b. An especially suitable reagent for the debromination of 1a-b leading to the natural compounds plumbagin (2a) and isoplumbagin (2b) is zinc-silver couple but Cl-elimination again occurs in traces only.

Mechanism of Conjugate Additions of Dialkylcuprates to Bromonaphthoquinones

The correlation of bromonaphthoquinone redox potentials with reactivity toward dialkylcuprates reveals that the conjugate addition of Gilman reagents to bromojuglones proceeds via a single-electron-transfer mechanism.

Enantioselective Nickel-Catalyzed Reductive Aryl/Alkenyl-Cyano Cyclization Coupling to All-Carbon Quaternary Stereocenters

An enantioselective nickel-catalyzed intramolecular reductive cross-coupling of C(sp2) electrophiles and cyano groups is reported. Enantioenriched CN-containing all-carbon quaternary stereocenters are assembled by desymmetrizing cyclization of aryl/alkeny

Catalyst-Controlled Transannular Polyketide Cyclization Cascades: Selective Folding of Macrocyclic Polyketides

The biomimetic synthesis of aromatic polyketides from macrocyclic substrates by means of catalyst-controlled transannular cyclization cascades is described. The macrocyclic substrates, which feature increased stability and fewer conformational states, were thereby transformed into several distinct polyketide scaffolds. The catalyst-controlled transannular cyclizations selectively led to aromatic polyketides with a defined folding and oxygenation pattern, thus emulating β-keto-processing steps of polyketide biosynthesis.

Ruthenium-catalyzed C-H oxygenation of quinones by weak O-coordination for potent trypanocidal agents

Ruthenium-catalysis enabled the C-5 selective C-H oxygenation of naphthoquinones, and also sets the stage for the site-selective introduction of a hydroxyl group into anthraquinones. A-ring modified naphthoquinoidal compounds represent an important class of bioactive quinones for which the present study encompasses the first C-H oxygenation strategy by weak O-coordination.