- Reductions of aromatic amino acids and derivatives
-
Catalytic reduction of phenylalanine and phenylglycine derivatives can be achieved with rhodium on carbon or alumina to give good yields of the corresponding cyclohexyl derivatives. The procedure can be scaled.
- Ager, David J.,Prakash, Indra
-
p. 164 - 167
(2013/09/05)
-
- Catalytic Hydrogenation of Chiral α-Amino and α-Hydroxy Esters at Room Temperature with Nishimura Catalyst without Racemization
-
The hydrogenation of carboxylic acid derivatives at room temperature was investigated. With a mixed Rh/Pt oxide (Nishimura catalyst), low to medium activity was observed for various α-amino and α-hydroxy esters. At 100 bar hydrogen pressure and 10% catalysts loading, high yields of the desired amino alcohols and diols were obtained without racemization. The most suitable α-substituents were NH2, NHR, and OH, whereas β-NH2 were less effective. Usually, aromatic rings were also hydrogenated, but with the free bases of amino acids as substrates, some selectivity was observed. No reaction was found for α-NR2, α-OR, and unfunctionalized esters; acids and amides were also not reduced under these conditions. A working hypothesis for the mode of action of the catalyst is presented.
- Studer, Martin,Burkhardt, Stefan,Blaser, Hans-Ulrich
-
p. 802 - 808
(2007/10/03)
-
- Probes of the Active Site of Norepinephrine N-Methyltransferase: Effect of Hydrophobic and Hydrophilic Interactions on Side-Chain Binding of Amphetamine and α-Methylbenzylamine
-
A series of ω-substituted analogues of amphetamine and α-methylbenzylamine were prepared and evaluated as inhibitors of norepinephrine N-methyltransferase (NMT).These included several alkyl side chain extended analogues (1-5), as well as the terminally hydroxylated derivatives phenylalanol (6a) and Phenylglycinol (7a).None of the alkyl-substituted derivatives displayed appreciable activity as inhibitors; however, the hydroxylated analogues were up to twofold more potent than the parent compounds.The positive contribution of the side-chain hydroxy suggests that theterminal methyl group of the lead compounds is situated close to a hydrophilic area or hydrogen bonding functional group within the active site.
- Grunewald, Gary L.,Monn, James A.,Rafferty, Michael F,,Borchardt, Ronald T.,Krass, Polina
-
p. 1248 - 1250
(2007/10/02)
-