199613-48-4Relevant academic research and scientific papers
Enantioselective Desymmetrization of cis-3,5- O-Arylidenecyclohexanones Catalyzed by Cinchona-Derived Quaternary Ammonium Salts
Cortigiani, Mauro,Gillick Healy, Malachi,Mereu, Andrea,Adamo, Mauro F. A.
, p. 4112 - 4119 (2019/04/30)
An enantioselective protocol for the desymmetrization of cis-3,5-O-arylidenecyclohexanones has been developed that proceeded under the catalysis of readily available and inexpensive Cinchona-derived quaternary ammonium salts. The synthetic relevance of the methodology was exemplified by the synthesis of a key intermediate that could be used in the preparation of the active pharmaceutical ingredient, paricalcitol (Zemplar).
Total Synthesis of Lycopalhine A
Ochi, Yuji,Yokoshima, Satoshi,Fukuyama, Tohru
, p. 96 - 114 (2016/12/24)
The total synthesis of lycopalhine A featuring the construction of a tricyclic system via cleavage of a cyclopropane ring and an ensuing intramolecular Michael addition, stereoselective introduction of a 2-aminoethyl moiety via a reaction of allyltrimethy
Synthesis of diastereomers of 1,3-cis-25-dihydroxy-19-norvitamin D3
Usuda, Kosuke,Biswas, Tanima,Yamaguchi, Takuya,Akagi, Yusuke,Yasui, Koji,Uesugi, Motonari,Shimizu, Isao,Hosokawa, Seijiro,Nagasawa, Kazuo
, p. 1190 - 1195 (2016/08/11)
1β,3β,25-Dihydroxy-19-norvitamin D3 (4a) and 1α,3α,25-dihydroxy-19-norvitamin D3 (4b) were synthesized by employing a new A-ring synthon, (1R,3S)-3-((tert-butyldimethylsilyl)oxy)-5-oxocyclohexyl benzoate (19), which was derived from D-(-)-quinic acid in 12 steps. The A-ring was coupled with the circular dichroism (CD) ring by means of Julia-Kocienski olefination to construct the diene unit. The structures of the products were confirmed by 1H-NMR and nuclear Overhauser effect (NOE) experiments.
Total syntheses of 2,2′-epi-cytoskyrin A, rugulosin, and the alleged structure of rugulin
Nicolaou,Yee, Hwee Lim,Piper, Jared L.,Papageorgiou, Charles D.
, p. 4001 - 4013 (2008/02/04)
The total syntheses of 2,2′-epi-cytoskyrin A, rugulosin, and the alleged structure of rugulin are described. These naturally occurring bisanthraquinones and their relatives are characterized by novel molecular architectures at the core, at which lies a mo
Total synthesis of (+)-rugulosin and (+)-2,2′-epi-cytoskyrin A through cascade reactions
Nicolaou,Lim, Yee Hwee,Papageorgiou, Charles D.,Piper, Jared L.
, p. 7917 - 7921 (2007/10/03)
(Chemical Equation Presented) The cytoskyrin cascade: The total syntheses of the bisanthraquinones 2 (+)-2,2′-epi-cytoskyrin A (R2 = OMe) and (+)-rugulosin (R2 = Me) has been achieved through a cascade sequence from anthradihydroquin
Chemical synthesis of optically active cis-cyclohexa-3,5-diene-1,2-diols and their 5-2H-derivatives
Hanazawa, Takeshi,Okamoto, Sentaro,Sato, Fumie
, p. 5455 - 5457 (2007/10/03)
A variety of optically active 3-substituted cis-cyclohexane-3,5-dien-1,2-diol acetonides were readily prepared from chiral 5-(tert-butyldimethylsilyloxy)-2-cyclohexenone through a seven-step reaction in good overall yield. The synthesis also allowed prepa
Synthesis of optically active 5-(tert-butyldimethylsiloxy)-2- cyclohexenone and its 6-substituted derivatives as useful chiral building blocks for the synthesis of cyclohexane rings. Synthesis of carvone, penienone, and penihydrone
Hareau, Georges P.-J.,Koiwa, Masakazu,Hikichi, Shinichi,Sato, Fumie
, p. 3640 - 3650 (2007/10/03)
Optically active 5-(tert-butyldimethylsiloxy)-2-cyclohexenone (1) and its 6-substituted derivatives 2a,b were synthesized from the readily available optically active ethyl 3-(tert-butyldimethylsiloxy)-5-hexenoate (4), where the Ti(II)-mediated intramolecular nucleophilic acyl substitution reaction and the FeCl3-mediated ring expansion reaction of a 1- hydroxybicyclo[3.1.0]hexane are the key reactions. The enone 1 reacted with higher-order cyanocuprates with excellent diastereoselectivity to afford the trans-addition products, trans-13, in excellent yields. The reaction of 1 with lower-order cyanocuprates proceeded with moderate to excellent syn- selectivity to afford cis-13. Treatment of trans- and cis-13 with DBU (1,8- diazabicyclo[5.4.0]undec-7-ene) or catalyst p-TSA (p-toluenesulfonic acid) resulted in a β-elimination reaction to furnish the corresponding optically active 5-substituted-2-cyclohexenones 14. The 1,4-addition reaction of 2a and 2b with organocy-anocuprates followed by treatment of the resulting 20 with DBU provided the 2,5-disubstituted-2-cyclohexenones 19 with excellent ee. The conversion of 14 into the 3,5-disubstituted-2-cyclohexenone 22 has also been carried out via 1,2-addition of alkyllithium onto the carbonyl group and the following oxidation with PCC (pyridinium chlorochromate). Similarly, the conversion of 19 into 2,3,5-trisubstituted-2-cyclohexenones 24 has been carried out. A highly efficient, first total synthesis of penienone 25 and penihydrone 26 has been accomplished. Thus, the 1,4-addition reaction of 1 with the (E,E)-1,3-heptadienyl cyanocuprate and consecutive trap of the resulting copper enolate with formaldehyde gave 28, which upon treatment with DBU or Pyr · HF yielded 25 and 26, respectively. An efficient synthesis of both enantiomers of carvone starting from (S)-20ab has been also accomplished.
Efficient and practical synthesis of optically active 5-t- butyldimethylsiloxy-2-cyclohexenone as a convenient chiral 2,5- cyclohexadienone synthon
Hikichi, Shinichi,Hareau, Georges P.-J.,Sato, Fumie
, p. 8299 - 8302 (2007/10/03)
An efficient and practical method for the preparation of optically active 5-t-butyldimethylsiloxy-2-cyclohexenone (3), a convenient chiral 2,5- cyclohexadienone synthon, from readily available ethyl 4-chloro-3-hydroxy- butyrate (7) has been on developed w
