CAS No 491-67-8 , 5,6,7-trihydroxy-2-phenylchromen-4-one

Title: Baicalein
CAS Registry Number: 491-67-8
CAS Name: 5,6,7-Trihydroxy-2-phenyl-4H-1-benzopyran-4-one
Synonyms: 5,6,7-trihydroxyflavone; noroxylin
Molecular Formula: C15H10O5
Molecular Weight: 270.24
Percent Composition: C 66.67%, H 3.73%, O 29.60%
Literature References: From roots of Scutellaria baicalensis. Isoln and structure: Bargellini, Gazz. Chim. Ital. 49, II, 47 (1919); Shibata et al., Acta Phytochim. 1, 109 (1923). Synthesis: Sastri, Seshadri, Proc. Indian Acad. Sci. 23A, 262 (1946), C.A. 41, 449 (1947); Sch?nberg et al., J. Am. Chem. Soc. 77, 5390 (1955); Jouanne, Mentzer, Compt. Rend. 254, 727 (1962); Agasimundin, Siddappa, J. Chem. Soc. Perkin Trans. 1 1973, 503. Pharmacology: Koda et al., C.A. 75, 47200d (1971).
Properties: Yellow prisms from alc, dec 264-265°. uv max (ethanol): 324, 276 nm (log e 4.18, 4.42). Sol in alcohol, methanol, ether, acetone, ethyl acetate, hot glacial acetic acid. Sparingly sol in chloroform, nitrobenzene. Practically insol in water. Sol in dil NaOH with greenish-brown color. Concd H2SO4 gives yellow color, green fluorescence.
Absorption maximum: uv max (ethanol): 324, 276 nm (log e 4.18, 4.42)
Therap-Cat: Astringent.
Keywords: Astringent.