Essential Oils and Their Constituents. XXI.¹ Isomerization of α-Humulene Monoxide to β-Humulen-7-ol. A New Sesquiterpene Alcohol

Abstract

tation broths of Bacillus subtilis,9 from cultures of Aspergillus niger,10 and as a product of tryptophane metabolism by claviceps Paspali.11 In general the odihydric phenolic structure is rare among microbial products.Experimental A sample (40 mg.) of the crude yellow amorphous phenolic metabolite was dissolved in a minimum quantity of boiling water. The aqueous solution was acidified with sulfuric acid and the free phenol was extracted with ethyl acetate. The ethyl acetate solution was treated with Darco G-60 activated carbon, filtered, and evaporated. The product was recrystallized twice from hot water.When the amorphous or colorless crystalline phenol was heated on a Kofler hot stage, it began to sublime at 140°and formed beautiful hard cubes, m.p. 204-205°( cor.). A mixture melting point determination with an authentic sample of 2,3-dihydroxybenzoic acid produced no melting point depression.

Hop aroma in American beer

“…The oxidation products Tressl observed are the ones that would be expected by air oxidation of humulene, according to the work of Pickett et al (1977). The observation of significant concentrations of humulene epoxide I and the absence of humulene epoxide I1 in the pilot brews as well as in the two commercial American beers may be due to acid catalysis (Nigam and Levi, 1964) of the humulene epoxide I1 to humulenol11, which was found in high concentrations. Humulenol I1 is the second most abundant oxidation product (0.05 % ), and humuladienone is not formed in any detectable quantities.…”

“…Humulenol I1 and humulene epoxide I1 were prepared (Damodaran and Dev, 1968) and purified (Nigam and Levi, 1964) by previously reported methods from humulene purchased from Tridom Chemical Corp., Hauppauge, NY. Humulenol I1 and humulene epoxide I1 were prepared (Damodaran and Dev, 1968) and purified (Nigam and Levi, 1964) by previously reported methods from humulene purchased from Tridom Chemical Corp., Hauppauge, NY.…”

Essential oils and their constituents. XLII. Isomerization of epoxides on active alumina

“…Experimental humulene oxide and caryophyllene oxide undergo Preparation of Epoxides of Linzorzene, a-Pirlet~e, and characteristic isomerizations to unsaturated Caryophyllene The hydrocarbons were allowed to react with equiduring chromatography On molar amounts of perphthalic acid in ether solution for alumina (1,2). Similar findings were made the rearrangement of trans-cyclodecene epoxide to an allylic alcohol during chromatography over strongly activated alumina (4).…”

Obtention de nouveaux squelettes diterpéniques lors de l'isomérisation d'époxydes diterpéniques sur alumine active

“…On observe deux effets significatifs : d'une part un effet a champ fort sur C-5 dQ a une interaction y-gauche H5/OH; et un effet a champ faible sur CH3-20, dQ a une disposition y-anti, transmis par un hydroxyle tertiaire (7,8).…”

“…Methyl 8,14P-epoxysandarcopimarate leads to bicyclic diterpene compounds by a Grob fragmentation, to derivatives of cleistanthane by a 1,2 migration of the vinyl substituent, as well as to one cycloditerpene compound. The 7,8 (or 8,9) derivatives of methyl isopimarate lead essentially to hydroxyolefins formed by a bifunctional acid-base mechanism at the alumina surface.…”