- Enzyme-mediated enantioselective hydrolysis of 1,2-diol monotosylate derivatives bearing an unsaturated substituent
-
We have succeeded in the easy preparation of optically active 1,2-diol monotosylates bearing an unsaturated substituent via enzymatic hydrolysis. Lipase PS quickly catalyzes the hydrolyses of 2-acetoxybut-3-enyl tosylate, which has a double bond, and 2-acetoxybut-3-ynyl tosylate, which has a triple bond, with excellent enantioselectivity to afford the corresponding optically active compounds. The reaction is also applicable to acetates with a longer chain, which has a double bond at the terminus. To demonstrate the applicability of this method, enantiomerically pure (R)-massoialactone, a natural coconut flavor, has been synthesized from racemic 2-acetoxypent-4-enyl tosylate in several steps. Furthermore, the enzyme can recognize the stereochemistry of olefins, and the (Z)-alkenyl structure is more suitable for the enantioselective hydrolysis than the (E)-isomer.
- Matsumoto,Oohana,Hashimoto,Usuda,Shimoda,Ohshima,Suzuki,Togawa
-
p. 3981 - 3988
(2018/06/15)
-
- An alternate synthesis of enantiomerically pure levetiracetam (Keppra)
-
A simple and efficient synthesis of levetiracetam has been achieved with high enantiopurity (>99%) starting from commercially available benzyl glycidyl ether. The method is amenable for industrial scale-up.
- Mujahid, M.,Mujumdar, P.,Sasikumar, M.,Kunte, S. S.,Muthukrishnan, M.
-
p. 1512 - 1515,4
(2012/12/12)
-
- An alternate synthesis of enantiomerically pure levetiracetam (Keppra)
-
A simple and efficient synthesis of levetiracetam has been achieved with high enantiopurity (>99%) starting from commercially available benzyl glycidyl ether. The method is amenable for industrial scale-up.
- Mujahid,Mujumdar,Sasikumar,Kunte,Muthukrishnan
-
p. 1512 - 1515
(2013/01/15)
-
- THERAPEUTIC COMPOUNDS
-
The invention relates to novel resolvin compounds and pharmaceutical preparations thereof. The invention further relates to methods of treatment using the novel resolvin compounds of the invention.
- -
-
Page/Page column 112
(2010/04/27)
-
- A short enantioselective synthesis of the antiepileptic agent, levetiracetam based on proline-catalyzed asymmetric α-aminooxylation
-
An efficient enantioselective synthesis of a new antiepileptic drug, levetiracetam is described, in high optical purity (>99.5% ee), using proline-catalyzed α-aminooxylation of n-butyraldehyde as the key step.
- Kotkar, Shriram P.,Sudalai, Arumugam
-
p. 6813 - 6815
(2007/10/03)
-
- Ring closing metathesis for the formation of medium ring ethers: The total synthesis of (-)-isolaurallene
-
The total synthesis of the marine metabolite (-)-isolaurallene is described. Two approaches to the core nine-membered ether are presented both of which are based on a ring closing metathesis to close the cyclic ether.
- Crimmins, Michael T,Emmitte, Kyle A,Choy, Allison L
-
p. 1817 - 1834
(2007/10/03)
-
- Synthesis of (+)-Homononactic Acid via Iodoetherification
-
(+)-Homononactic acid, one of the monomers of polynactin, and its 8-epimer were synthesized. The key step was cis-selective iodoetherification of the enone or the α-silyloxyolefin intermediates constructed with Wittig-Horner or Julia coupling reactions, r
- Kiyota, Hiromasa,Abe, Masaki,Ono, Yukie,Oritani, Takayuki
-
p. 1093 - 1095
(2007/10/03)
-