5287. Kawain

Nomenclature

CAS number: 500-64-1
(6R)-5,6-Dihydro-4-methoxy-6-[(1E)-2-phenylethenyl]-2H-pyran-2-one; 5-hydroxy-3-methoxy-7-phenyl-2,6-heptadienoic acid δ-lactone; 4-methoxy-6-(β-phenylvinyl)-5,6-dihydro-α-pyrone; 4-methoxy-6-styryl-5,6-dihydro-α-pyrone; kavain; gonosan.
C14H14O3; mol wt 230.26.
C 73.03%, H 6.13%, O 20.85%.

Description and references

From the rhizome and roots of Piper methysticum Forst., Piperaceae (kava): Borsche, Peitzsch, Ber. 63, 2414 (1930); Hnsel, Beiersdorff, Naturwissenschaften 45, 573 (1958); eidem, Arzneim.-Forsch. 9, 581 (1959). Synthesis: Fowler, Henbest, J. Chem. Soc. 1950, 3642; Kostermans, Nature 166, 788 (1950); idem, Rec. Trav. Chim. 70, 79 (1951); Z. H. Israili, E. E. Smissman, J. Org. Chem. 41, 4070 (1976). Abs config: Snatzke, Hnsel, Tetrahedron Lett. 1968, 1797. Crystal and molecular structure: A. Yoshino, W. Nowacki, Z. Kristallogr. Kristallgeom. Kristallphys. Kristallchem. 136, 66 (1972), C.A. 78, 63591z (1973).

Chemical structure

Properties

Rods from methanol + ether, mp 105-106°. bp0.1 195-197°. [α]D20 +105° (abs alc). uv max (methanol): 210, 245, 282 nm (log ε 4.38, 4.44, 2.81). Practically insol in water. Sol in acetone, ether, methanol; slightly sol in hexane.

Derivative

(±)-Form.

Nomenclature

CAS number: 3155-48-4

Properties

Needles from methanol, mp 146-147°.

Derivative

Dihydrokawain.

Nomenclature

CAS number: 587-63-3
Marindinin.
C14H16O3; mol wt 232.28.
C 72.39%, H 6.94%, O 20.66%.

Properties

Crystals from ether, mp 58-60°. [α]D24 +31° (methanol). uv max (methanol): 236 nm (log ε 4.14). Sol in alc, chloroform; moderately sol in ether. Practically insol in petr ether, water.