Total syntheses of (+)-bernumidine and its unnatural enantiomer

Recent Advances in the Enantioselective Synthesis of Chiral Amines via Transition Metal-Catalyzed Asymmetric Hydrogenation

“…The catalytic system was extended to a variety of 2-enamido-heteroarenes with excellent results (up to 99% ee), thus providing efficient access to 2-aminoethyl-arenes, which are useful building blocks in medicinal chemistry. Of note, the rhodium-catalyzed AH of acetamidoacrylates or vinylacetamides has been widely used as a powerful tool in total synthesis of natural products , and for the preparation of drugs and pharmacologically active compounds. − …”

Chemoenzymatic approaches to plant natural product inspired compounds

“…Hydrolysis of the carbamate gave (R)-9 and subsequent chemical transformations generated (R)-8, in an overall six-step route from (rac)-9, in 39% yield and 99% ee. 20 Morphine and analogues are attractive synthetic targets, however, the complexity of the molecular scaffold has made cost-effective, scalable syntheses somewhat elusive. Signicant efforts towards these compounds by the Hudlicky group over the past 25 years have involved a chemoenzymatic approach.…”

“…Hydrolysis of the carbamate gave ( R )- 9 and subsequent chemical transformations generated ( R )- 8 , in an overall six-step route from ( rac )- 9 , in 39% yield and 99% ee. 20…”

The role of biocatalysis in the asymmetric synthesis of alkaloids – an update

“…72 Due to the success of Scheme 13 Lipase-catalysed kinetic resolution of building block 85 in the asymmetric synthesis of (À)-sparteine bissulfate (90). Scheme 14 Hydrolytic kinetic resolution of lactone 91 by horse liver esterase (HLE) used in the chemo-enzymatic synthesis of (R)-harmonine (94). arene cis-dihydrodiols as chiral building blocks, several of these compounds are now commercially available (for examples, see Scheme 15b), making them accessible also to researchers that lack the necessary equipment or expertise for carrying out TDO biotransformations.…”

“…In a recent example, the literature-known 93 DKR of rac -174 using lipase from Candida rugosa in combination with an iridium( iii )-based racemisation catalyst was used to obtain the carbamate ( R )-176 in 68% yield and 99% ee ( Scheme 21 ). 94 Hydrolysis of 176 gave ( R )-salsolidine, which was further transformed into (+)-bernumidine (177), an alkaloid of Berberis nummularia .…”