- Synthesis of Terpenes Containing the Bicycloheptane Ring System by the Intramolecular Cycloaddition Reaction of Vinylketenes with Alkenes. Preparation of Chrysanthenone, β-Pinene, β-cis-Bergamotene, β-trans-Bergamotene, β-Copaene, and β-Ylangene and Lemnalol
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Treatment of geranoyl chloride (20) with triethylamine in toluene at reflux gave the vinylketene 21 which underwent a cycloaddition to give 7,7-dimethyl-2-methylenebicycloheptan-6-one (24) in 43percent yield.Isomerization over Pd gave chrysanthenone (6) in quantitative yield.Wolf-Kischner reduction gave β-pinene (5) in 70percent yield.A similar sequence of reactions starting from (Z,E)- and (E,E)-farnesoyl chloride gave ketones 51 and 57, which were converted to β-cis-bergamotene (8) and β-trans-bergamotene (9), respectively. β-Copaene (10) and β-ylangene (11) were prepared from 57 by a three-step sequence.Treatment of the imidazole 59 with tri-n-butyltin hydride in toluene at reflux gave a 46percent yield of a 1:1 mixture of 10 and 11.Selenium dioxide oxidation of 11 gave the antitumor agent lemnalol.The mechanisms of the regiospecific ketene generation and the cycloaddition reaction have been explored, and the reactivity of the novel bicycloheptanones has been examined.
- Kulkarni, Yashwant S.,Niwa, Maho,Ron, Eyal,Snider, Barry B.
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- Amides as bioisosteres of triazole-based geranylgeranyl diphosphate synthase inhibitors
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Geranylgeranyl diphosphate synthase (GGDPS) inhibitors are of potential therapeutic interest as a consequence of their activity against the bone marrow cancer multiple myeloma. A series of bisphosphonates linked to an isoprenoid tail through an amide linkage has been prepared and tested for the ability to inhibit GGDPS in enzyme and cell-based assays. The amides were designed as analogues to triazole-based GGDPS inhibitors. Several of the new compounds show GGDPS inhibitory activity in both enzyme and cell assays, with potency dependent on chain length and olefin stereochemistry.
- Goetz, Daniel B.,Holstein, Sarah A.,Varney, Michelle L.,Wiemer, David F.
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- Iron-Catalyzed, Fluoroamide-Directed C-H Fluorination
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This communication describes a mild, amide-directed fluorination of benzylic, allylic, and unactivated C-H bonds mediated by iron. Upon exposure to a catalytic amount of iron(II) triflate (Fe(OTf)2), N-fluoro-2-methylbenzamides undergo chemoselective fluorine transfer to provide the corresponding fluorides in high yield. The reaction demonstrates broad substrate scope and functional group tolerance without the use of any noble metal additives. Mechanistic and computational experiments suggest that the reaction proceeds through short-lived radical intermediates with F-transfer mediated directly by iron.
- Groendyke, Brian J.,Abusalim, Deyaa I.,Cook, Silas P.
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supporting information
p. 12771 - 12774
(2016/10/13)
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- Synthesis and fungicidal activities of (Z/E)-3,7-dimethyl-2,6-octadienamide and its 6,7-epoxy analogues
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In order to find new lead compounds with high fungicidal activity, (Z/E)-3,7-dimethyl- 2,6-octadienoic acids were synthesized via selective two-step oxidation using the commercially available geraniol/nerol as raw materials. Twenty-eight different (Z/E)-3,7-dimethyl-2,6-octadienamide derivatives were prepared by reactions of (Z/E)-carboxylic acid with various aromatic and aliphatic amines, followed by oxidation of peroxyacetic acid to afford their 6,7-epoxy analogues. All of the compounds were characterized by HR-ESI-MS and 1H-NMR spectral data. The preliminary bioassays showed that some of these compounds exhibited good fungicidal activities against Rhizoctonia solani (R. solani) at a concentration of 50 μg/mL. For example, 5C, 5I and 6b had 94.0%, 93.4% and 91.5% inhibition rates against R. solani, respectively. Compound 5f displayed EC50 values of 4.3 and 9.7 μM against Fusahum graminearum and R. Solani, respectively.
- Yang, Mingyan,Dong, Hongbo,Jiang, Jiazhen,Wang, Mingan
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p. 21023 - 21036
(2016/01/25)
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- GGA AND GGA DERIVATIVES COMPOSITIONS THEREOF AND METHODS FOR TREATING NEURODEGENERATIVE DISEASES INCLUDING PARALYSIS INCLUDING THEM
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This invention relates to geranylgeranyl acetone (GGA) derivatives and the use of GGA, its isomers, and GGA derivatives in methods for inhibiting neural death, increasing neural activity, increasing axon growth and cell viability, and increasing the survival rate of subjects administered the GGA or GGA derivatives.
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Paragraph 0440
(2014/10/18)
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- A short synthesis of (+)-bakuchiol
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The concise enantioselective total synthesis of (+)-bakuchiol has been achieved using an asymmetric 1,4-addition to construct its all-carbon chiral quaternary center based on the induction of chirality by the (2′S)-2′-phenyloxazolidinone auxiliary, followed by a one-pot transformation under aldol reaction conditions. The synthesis was completed in four steps from (E)-geranic acid in an overall yield of 53%. Georg Thieme Verlag Stuttgart · New York.
- Esumi, Tomoyuki,Yamamoto, Chihiro,Fukuyama, Yoshiyasu
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p. 1845 - 1847
(2013/09/12)
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- A new synthesis of pteridines substituted with branched and linear alkenyl groups at C(6). The nitroso-ene reaction of 4-(alkenoylamino)-5- nitrosopyrimidines
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Pteridines substituted with a 1,1-, 1,2-, or 1,1,3-substituted alkenyl group (mostly (is)-configured) at C(6) were synthesized in high yields by the intramolecular nitroso-ene reaction of 4-(alkenoylamino)-2-amino-6-benzyloxy-5- nitroso- and 4-(alkenoylamino)-2,6-diamino-5-nitrosopyrimidines. Thus, the N-alkenoyl nitrosopyrimidines 4 and 5 provided the pteridines 6 and 7, respectively, characterized by a 1,2-disubstituted (E)-alkenyl substituent, the C(4)-(E)-geranoyl amide 13 led regio- and stereoselectively to the (E)-1,1,2-trisubstituted alkenyl-pteridine 16, and the C(4)-(Z) isomer 14 led to 17 possessing a 1,1-disubstituted alkenyl group. The trifluoromethylated butenoyl amide 15 possessing a less highly nucleophilic alkenoyl group reacted more slowly to give the trifluoromethylated vinylpteridine 18. Also the 4-(alkenoylamino)-2,6-diamino-5-nitrosopyrimidine 20 reacted more slowly than 4 and 5, and provided the pteridines 23; introduction of additional N-acyl groups as in 21 and 22 led to a considerably faster ene reaction. The X-ray crystal structure analysis of the nitroso amide 15 shows eight symmetrically independent molecules in the unit cell. In the crystalline state, the N,N- dimethylformamidine derivative 9 of 6 forms a centrosymmetric dimer with the 7,8-lactam group connected by intermolecular hydrogen bonds.
- Zhang, Fang-Li,Schweizer, W. Bernd,Xu, Ming,Vasella, Andrea
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p. 521 - 534
(2008/02/07)
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- ANTIMICROBIAL ACTIVE PREPARATIONS
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The invention relates to the use of perillic, geranic and citronella acids, the derivatives thereof and citronrllol derivatives in the form of antimicrobial active agents against bacteria, yeast and/or mildew, microorganisms hereafter. Said invention relates, in particular to the use of said antimicrobial active agents for producing cosmetic and pharmaceutical preparations, food product and animal food compounds. Natural monotherpenes and the derivatives of the oxidation products thereof as the antimicrobial active agents are also disclosed.
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Page/Page column 43
(2008/06/13)
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- EFFICIENT ASYMMETRIC HYDROGENATIONS OF CAMPHOR-SULTAM-IMIDE-CONJUGATED ALKENES.
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The trisubstituted olefinic bond of sultam-imides 2 was hydrogenated in the presence of Pd/C with >90percent diastereoface discrimination to give after saponification recovered auxiliary 7 and the β-substituted carboxylic acids 5 or 6 in high e.e..
- Oppolzer, Wolfgang,Mills, Robert J.,Reglier, Marius
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p. 183 - 186
(2007/10/02)
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- Intramolecular Cycloadditions of Ketenes. 2. Synthesis of Crysanthenone, β-Pinene, β-cis-Bergamotene, and β-trans-Bergamotene
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Vinylketenes prepared from geranoyl and farnesoyl chloride by treatment with triethylamine react to give bicycloheptanones which can be converted to β-pinene and the β-bergamotenes by Wolff-Kishner reduction.
- Kulkarni, Yashwant S.,Snider, Barry B.
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p. 2809 - 2810
(2007/10/02)
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- CITRONELLYL CITRONELLATE AND CITRONELLYL GERANATE IN THE EUROPEAN HORNET, Vespa crabro (HYMENOPTERA: VESPIDAE)
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Citronellyl citronellate and citronellyl geranate, new insect natural products, have been identified in the van der Vecht's gland of the European hornet.
- Wheeler, J. W.,Ayorinde, F. O.,Greene, A.,Duffield, R. M.
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p. 2071 - 2072
(2007/10/02)
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