A new anthraquinone (3,8-dihydroxy-2-methyl anthraquinone), named tectone (1), along with fourteen known compounds (2-15) comprised of five terpenoids (2-5, 15), four flavonoids (6-9), three flavone glycosides (10-12), and two phenolic glycosides (13-14) were isolated from the chloroform and n-butanol fractions of the ethanol extract of Tectona grandis leaves. Attempts were made to synthesize compound 1. This resulted in the synthesis of three additional anthraquinones (16-18), out of which compound 16 is new. The structures of all compounds were established by spectral analysis. The isolated and synthesized compounds were evaluated for their antihyperglycemic activity. Compounds 1, 2, 4 and 14 showed significant antihyperglycemic activity in streptozotocin-induced diabetic rats at a dose of 100 mg/kg body weight, which is comparable to the standard drug metformin.
WarrierPS. (1994) Indian Medicinal Plants, Ist ed. Orient Longman Pvt. Ltd.New Delhi, India, 245–248;
2.
WarrierPK, RamankuttyC, NairRV, NambairVPK. (1996) Indian Medicinal Plants, Orient Longman Pvt. Ltd.New Delhi, India, 5, 245–247.
3.
MajumdarM, NayeemN, KamatJV, AsadMd. (2007) Evaluation of Tectona grandis leaves for wound healing activity. Pakistan Journal of Pharmaceutical Sciences, 20, 120–124;
4.
DialloA, GbeassorM, VovorA, Eklu-GadegbekuK, AklikokouK, AgbononA, AbenaAA, de-SouzaC, AkpaganaK. (2008) Effect of Tectona grandis on phenylhydrazine-induced anaemia in rats. Fitoterapia, 79, 332–336;
5.
GhaisasM, NavghareV, TakawaleA, ZopeV, TanwarM, DeshpandeA. (2009) Effect of Tectona grandis Linn. on dexamethasone-induced insulin resistance in mice. Journal of Ethnopharmacology, 122, 304–307.
6.
GhaisasM, NavghareV, TakawaleA, ZopeV, TanwarM, DeshpandeA. (2008) In-vitro antioxidant activity of Tectona grandis Linn. Phamacologyonline, 3, 296–305.
GuptaPK, SinghP. (2004) A naphthoquinone derivative from Tectona grandis Linn. Journal of Asian Natural Products Research, 6, 237–240;
9.
SumthongP, DamveldRA, ChoiYH, ArentshorstM, RamAFJ, HondellVD, CeesAMJJ, VerpoorteR. (2006) Activity of quinones from teak (Tectona grandis). Planta Medica, 72, 943–944;
10.
GoelRK, PathakNKR, BiswasM, PandeyVB, SanyalAK. (1987) Effect of lapachol a naphthaquinone isolated from Tectona grandis, on experimental peptic ulcer and gastric secretion. Journal of Pharmacy and Pharmacology, 39, 138–140;
11.
KhanRM, MlungwanaSM. (1999) 5-Hydroxylapachol: a cytotoxic agent from Tectona grandis. Phytochemistry, 50, 439–442;
12.
KawazuK, MarwaniE, KobayashiA, NitodaT, KanzakiH. (1998) Production of antibacterial triterpene acids not detected in the native plant by cell suspension culture of Tectona grandis. Scientific Reports of the Faculty of Agriculture Okayama University, 87, 9–12.
13.
JohnIO, AlexanderGI. (2008) Friedelanone and other triterpenoids from Hymenocardia acida. International Journal of Physical Sciences, 3, 156–158;
WagnerH, BladtS, ZgainskyEM. (1984) Plant Drug Analysis: A Thin Layer Chromatographic Atlas.Springer-Verlag, Berlin.
24.
DhananjeyanMR, MilevYP, KronMA, NairMG. (2005) Synthesis and activity of substituted anthraquinones against a human filarial parasite, Brugia malayi. Journal of Medicinal Chemistry, 48, 2822–2830;
25.
SavardJ, BrassardP. (1984) Reactions of ketene acetals-14. The use of simple mixed vinylketene acetals in the annulation of quinines. Tetrahedron, 40, 3455–3464;
26.
RaiKN, PrasadSN (1994) Chemical examination of the stem of Cassia alata Linn. Journal of Indian Chemical Society, 71, 653–654.
27.
MauryaR, AkankshaJayendra, SinghAB, SrivastavaAK. (2008) Coagulanolide, a withanolide from Withania coagulans fruits and antihyperglycemic activity. Bioorganic & Medicinal Chemistry Letters, 18, 6534–6537.
