Title: Colforsin
CAS Registry Number: 66575-29-9
CAS Name: (3R,4aR,5S,6S,6aS,10S,10aR,10bS)-5-(Acetyloxy)-3-ethenyldodecahydro-6,10,10b-trihydroxy-3,4a,7,7,10a-pentamethyl-1H-naphtho[2,1-b]pyran-1-one
Additional Names: 7b-acetoxy-8,13-epoxy-1a,6b,9a-trihydroxylabd-14-en-11-one; forskolin; boforsin (obsolete)
Manufacturers' Codes: HL-362
Molecular Formula: C22H34O7
Molecular Weight: 410.50
Percent Composition: C 64.37%, H 8.35%, O 27.28%
Literature References: Diterpene isolated from Coleus forskohlii, Briq. Labiatae, possessing vasodilating and cardiostimulatory properties. Isoln and characterization: S. V. Bhat et al., Tetrahedron Lett. 1977, 1669; eidem, DE 2557784; eidem, US 4088659 (1977, 1978 both to Hoechst). Synthesis by hydroxylation of 9-deoxyforskolin: N. J. Hrib, Tetrahedron Lett. 28, 19 (1987); see also F. E. Ziegler et al., J. Am. Chem. Soc. 109, 8115 (1987). Stereocontrolled synthesis of the 3-ring system: S. Hashimoto et al., Chem. Commun. 1987, 24. Total synthesis of (±)-forskolin: S. Hashimoto et al., J. Am. Chem. Soc. 110, 3670 (1988); E. J. Corey et al., ibid. 3672. Positive inotropic and blood-pressure lowering activity: E. Lindner et al., Arzneim.-Forsch. 28, 284 (1978). Activates adenylate cyclase: H. Metzger, E. Lindner, ibid. 31, 1248 (1981). Binds to catalytic site of adenylate cyclase: T. Pfeuffer, H. Metzger, FEBS Lett. 146, 369 (1982). Lowers intraocular pressure: J. Capriolli, M. Sears, Lancet 1, 958 (1983). In treatment of glaucoma: eidem, US 4476140 (1984 to Yale University). Reviews: K. B. Seaman, J. W. Daly, J. Cyclic Nucleotide Res. 1981, 201; K. B. Seaman, "Forskolin and Adenylate Cyclase: New Opportunities in Drug Design" in Annu. Rep. Med. Chem. 19, D. M. Bailey, Ed. (Academic Press, New York, 1984) pp 293-302.
Properties: Colorless crystals from ethyl acetate/petr ether, mp 230-232°. uv max 210, 305 nm (e 1000, 50). [a]D25 -26.19° (c = 1.68 in CHCl3).
Melting point: mp 230-232°
Optical Rotation: [a]D25 -26.19° (c = 1.68 in CHCl3)
Absorption maximum: uv max 210, 305 nm (e 1000, 50)
Use: In purification of adenylate cyclase. |