Naphthoquinone

Naphthoquinone is a class of natural phenols based on the C6-C4 skeleton.

1,4-Naphthoquinone can be viewed as derivatives of naphthalene through the replacement of two hydrogen atoms by two ketone groups.

The name is also used generically for two other isomers:

• 1,2-Naphthoquinone
• 1,4-Naphthoquinone
• 2,6-Naphthoquinone (amphi-naphthoquinone)

Naturally occurring naphtoquinones

• Juglone
• Plumbagin
• Droserone

Properties

1,4-Naphthoquinone forms yellow triclinic crystals and has an odor similar to benzoquinone. It is sparingly soluble in cold water, slightly soluble in petroleum ether, and freely soluble in most polar organic solvents. In alkaline solutions it produces a reddish-brown color. Because of their aromatic stability, 1,4-naphthoquinone derivatives are known to possess anti-bacterial and anti-tumor properties.

Naphthoquinone forms the central chemical structure of many natural compounds, most notably the K vitamins.

Medicinal uses

Naphthoquinone derivatives have significant pharmacological properties. They are cytotoxic, they have significant antibacterial, antifungal, antiviral, insecticidal, anti-inflammatory, and antipyretic properties. Plants with naphthoquinone content are widely used in China and the countries of South America, where they are used to treat malignant and parasitic diseases.^[2]

See also

• Hydroxynaphthoquinone
• 1,4-Benzoquinone
• Plumbagin
• Quinone

References

1. ^ Merck Index, 11th Edition, 6315.
2. ^ Babula, P; Adam, V; Havel, L; Kizek, R (2007). "Naphthoquinones and their pharmacological properties". Ceska a Slovenska farmacie : casopis Ceske farmaceuticke spolecnosti a Slovenske farmaceuticke spolecnosti 56 (3): 114–20. PMID 17867522.