Chemical and chemoenzymatic routes to bridged homoarabinofuranosylpyrimidines: Bicyclic AZT analogues

• Sandeep Kumar,
• Jyotirmoy Maity,
• Banty Kumar,
• Sumit Kumar and
• Ashok K. Prasad

Beilstein J. Org. Chem. 2022, 18, 95–101, doi:10.3762/bjoc.18.10

• ) immobilized on polyacrylate (Lewatit), commonly known as Novozyme® 435 and Thermomyces lanuginosus lipase immobilized on silica, commonly known as Lipozyme® TL IM in different organic solvents, such as THF, acetonitrile, toluene, acetone, DIPE and 2-Me-THF. Vinyl acetate was used as acetyl donor at

• starting from diacetone ᴅ-glucofuranose were found to be 33.9 and 35.1%, respectively. In our earlier research work, bridged homolyxofuranosylpyrimidines were synthesized following a chemoenzymatic methodology where biocatalyst Novozyme 435 was used for regioselective acetylation of the primary hydroxy

A comprehensive review of flow chemistry techniques tailored to the flavours and fragrances industries

• Guido Gambacorta,
• James S. Sharley and
• Ian R. Baxendale

Beilstein J. Org. Chem. 2021, 17, 1181–1312, doi:10.3762/bjoc.17.90

Thiol-free chemoenzymatic synthesis of β-ketosulfides

• Adrián A. Heredia,
• Martín G. López-Vidal,
• Marcela Kurina-Sanz,
• Fabricio R. Bisogno and
• Alicia B. Peñéñory

Beilstein J. Org. Chem. 2019, 15, 378–387, doi:10.3762/bjoc.15.34

• chemoenzymatic synthesis of β-ketosulfides. One-pot two-step preparation of phenacylalkylsulfides. aReaction conditions: i. α-haloketone (0.25 mmol), potassium thioacetate (1.1 equiv), alkyl halide (1.1 equiv) and K2CO3 (2.0 equiv) in 500 µL of DMSO, 5 h at room temperature; ii. 100 mg of CAL-B (Novozyme 435

Enzymatic separation of epimeric 4-C-hydroxymethylated furanosugars: Synthesis of bicyclic nucleosides

• Neha Rana,
• Manish Kumar,
• Vinod Khatri,
• Jyotirmoy Maity and
• Ashok K. Prasad

Beilstein J. Org. Chem. 2017, 13, 2078–2086, doi:10.3762/bjoc.13.205

• , which is a key precursor for the synthesis of different types of bicyclic/spiro nucleosides, led to the formation of an inseparable 1:1 mixture of the desired product and 4-C-hydroxymethyl-1,2-O-isopropylidene-α-D-xylofuranose. A convenient environment friendly Novozyme®-435 catalyzed selective

• : bicyclonucleosides; biocatalysis; lipase; Novozyme®-435; separation of epimers; Introduction Sugar-modified bicyclic nucleosides have drawn the attention of synthetic chemists because of their effect on the conformational restriction of the furanose moiety of the nucleoside [1][2][3][4][5][6][7][8][9]. The

• lipase as biocatalyst. Similar applications of lipases have been reported for the separation of mixtures of arabinofuranosyl and -pyranosyl nucleosides [12], O-aryl α,β-D-ribofuranosides, etc. [13][14][15]. We herein report for the first time the use of Novozyme®-435 for the separation of an epimeric

Dicarboxylic esters: Useful tools for the biocatalyzed synthesis of hybrid compounds and polymers

• Ivan Bassanini,
• Karl Hult and
• Sergio Riva

Beilstein J. Org. Chem. 2015, 11, 1583–1595, doi:10.3762/bjoc.11.174

• fungal β-N-acetylhexosaminidase evaluated [28]. Similarly, dimers of sylibin (11a,b, Figure 3) and dehydrosylibin, obtained by Novozyme 435-catalyzed acylation with the divinyl esters of dodecanedioc acid, were evaluated in terms of antioxidant activity and cytotoxicity [29]. The obvious hypothesis

• acylation [30]. As shown in Scheme 2, the protease thermolysin catalyzed the regioselective acylation of the side chain of paclitaxel (12) to give the 2’-vinyl adipate 12a in 60% isolated yields. Novozyme 435-catalyzed elaboration of this intermediate allowed either to hydrolyze the residual vinyl ester to

• once again the well-known efficiency, selectivity and versatility of CAL-B (Novozyme 435) [16]. As in the previous examples, the mixed esters from the first esterification step can be used as acylating agents in the second esterification step. Scheme 3 shows the synthesis of the hybrid compounds 17 and