Constituents of black pepper. Some sesquiterpene hydrocarbons

Abstract

Individual sesquiterpene hydrocarbons were isolated from black pepper oil by column chromatography followed by preparative and capillary gas chromatography. On the basis of matching retentions, infrared and, where applicable, ultraviolet spectra of isolated components, the following were identified as major compounds of the sesquiterpene hydrocarbon fraction: -elemene, -copaene, /3-elemene, a-m-bergamotene, -santaíene, a-rra«s-bergamotene, /3-caryophyllene, -humulene, /3-selinene, aselinene, /3-bisabolene, -cadinene, and calamenene.

Chemical constituents of peppers (Piper spp.) and application to food preservation: naturally occurring antioxidative compounds.

“…Piperine [1] showed no activity. All phenolic amides [2][3][4][5][6] showed significant activity, more effective than cx-tocopherol at the same concentration (0.01%). The activity of compound [5] was as high as that of synthetic antioxidants, BHA and BHT, at the same level.…”

“…We studied the genus Piper of the Family Piperaceae, to identify the structure of the compounds in its species that give organoleptic (3)(4)(5), medicinal (6)(7)(8)(9), and insecticidal (10)(11)(12)(13) properties. Many species, among the 700 in this genus, are used not only as spices but also as folk medicines (14).…”

Chemotype Analysis and Antimicrobial Activities of Essential Oils from Fresh and Sun-Dried Berries of Piper guineense (Schum. and Thom)

“…In previous studies, isolation and characterization of terpene hydrocarbons from Piper guineense essential oil have been undertaken through matching of retention indices, infrared and UV spectra. The components identified were δ-elemene, α-copaene, β-elemene, α-cis-bergamotene, α-santalene, α-transbergamotene, β-caryophyllene, α-humulene, β-selinene, α-selinene, β-bisabolene, δ-cadinene and calamenene [17].…”

Di-tert-butylcyclopropenone and substituted di-tert-butyl-cyclopropenyl cations

“…2c,d,s O 1 Photolysis of a 3 % solution of 1 in ether at 2537 A (n -7 * excitation) resulted in decarbonylation with the formation of di-r-butylacetylene.9 Pyrolysis2c,d of 1 in a sealed tube under reduced pressure at 320-327°a fforded the same result. This reaction which is apparently general might serve as a convenient synthetic route (7) For a discussion of the ultraviolet absorption spectra of dialkylcyclopropenones see ref 2d and A. Krebs and B. Schrader, Justus Liebigs Ann. Chem., 709, 46(1967).…”

“…(2Í) For a good discussion of carbonium ions see D. Bethell and V. Gold, "Carbonium Ions," Academic Press Inc., New York, N. Y., It was of interest to attempt the synthesis of the extremely hindered tetra-i-butylcyclopropene (7) via the reaction of 5d with /-butyllithium in benzene. However, only reduction with the formation of 1,2,3-tri-/butylcyclopropene (8) and presumably isobutylene was observed.…”