Scalability of U-Shape Magnetic Nanoparticles-Based Microreactor–Lipase-Catalyzed Preparative Scale Kinetic Resolutions of Drug-like Fragments

Abstract

The production of active pharmaceutical ingredients (APIs) and fine chemicals is accelerating due to the advent of novel microreactors and new materials for immobilizing customized biocatalysts that permit long-term use in continuous-flow reactors. This work studied the scalability of a tunable U-shape magnetic nanoparticles (MNPs)-based microreactor. The reactor consisted of a polytetrafluoroethylene tube (PTFE) of various inner diameters (ID = 0.75 mm, 1.50 mm, or 2.15 mm) and six movable permanent magnets positioned under the tube to create reaction chambers allowing the fluid reaction mixture to flow through and above the enzyme-loaded MNPs anchored by permanent magnets. The microreactors with various tube sizes and MNP capacities were tested with the preparative scale kinetic resolution of the drug-like alcohols 4-(3,4-dihydroisoquinolin-2(1H)-yl)butan-2-ol (±)-1a and 4-(3,4-dihydroquinolin-1(2H)-yl)butan-2-ol (±)-1b, utilizing Lipase B from Candida antarctica immobilized covalently onto MNPs, leading to highly enantioenriched products [(R)-2a,b and (S)-1a,b]. The results in the U-shape MNP flow reactor were compared with reactions in the batch mode with CaLB-MNPs using similar conditions. Of the three different systems, the one with ID = 1.50 mm showed the best balance between the maximum loading capacity of biocatalysts in the reactor and the most effective cross-section area. The results showed that this U-shaped tubular microreactor might be a simple and flexible instrument for many processes in biocatalysis, providing an easy-to-set-up alternative to existing techniques.

Wall‐Immobilized Biocatalyst vs. Packed Bed in Miniaturized Continuous Reactors: Performances and Scale‐Up

“…Several points to address are reported using static beads and/or magnetic particle layers such as reactor plugging [82,83] and non-uniform flow velocity. [84] An interesting alternative is the combination of magnetic mixing and retention with magnetic bead movement. The needs for an easy and adjustable controlled magnetic field, that does not generate heat or cause particles to agglomerate are the new challenges to be tackled with these fluidized magnetic beads.…”

“…With magnetic particles, the handling and separation of immobilized enzymes after deactivation is facilitated by the use magnets or a magnetic field. Several points to address are reported using static beads and/or magnetic particle layers such as reactor plugging [82,83] and non‐uniform flow velocity [84] . An interesting alternative is the combination of magnetic mixing and retention with magnetic bead movement.…”

Immobilization of Lipase B from Candida antarctica on Magnetic Nanoparticles Enhances Its Selectivity in Kinetic Resolutions of Chiral Amines with Several Acylating Agents

“…Yield: 29 mg, 31 % (ee = 99.5%, by GC); 1 H NMR (500 MHz, chloroform-d 3 , δ ppm): 8.62 (s, 1H), 4.00 (p, J = 7.0 Hz, 2H), 3.38 (s, 2H), 1.54-1.43 (m, 2H), 1.39-1.26 (m, 6H), 1.20 (d, J = 6.6 Hz, 2H), 0.91 (t, J = 6.5 Hz, 3H); 13 The U-shape MNP reactor system (Figure 1), similar to its nonthermostatted predecessor [9], was designed using AutoCAD (2020 student version) and printed with a Rankfor100 3D printer (CEI Conrad Electronic International, Ltd., New Territories, Hong Kong). In this study, we used neodymium disc magnets, 4 mm × 2 mm, N35 (Euromagnet Ltd., Budapest, Hungary) as permanent magnets and a polytetrafluoroethylene (PTFE) tube with ID 1.50 mm as the reactor body and connection parts.…”

“…However, like every other free enzyme, it can have several limitations, such as instability, nonreusability, and sensitivity to several reactants, which immobilization can circumvent [6]. The immobilized forms of this versatile biocatalyst have been used for the KR of chiral alcohols [7][8][9][10], azolides [11], and amines [12][13][14][15][16][17].…”

“…Numerous researchers combined the advantages of MNP-immobilized biocatalysts and microreactor technology. In recent studies, a simple but effective and convenient MNPbased PTFE tube microreactor with six adjusting permanent magnets underneath the tube was used for the enantiomer selective acylation of drug-like racemic alcohols such as 4-(morpholin-4-yl)butan-2-ol [8], 4-(3,4-dihydroisoquinolin-2(1H)-yl)butan-2-ol, and 4-(3,4-dihydroquinolin-1(2H)-yl)butan-2-ol [9], catalyzed using a biocatalyst obtained via the covalent immobilization of lipase B from Candida antarctica on magnetic nanoparticles (CaLB-MNPs) in a continuous-flow mode. To broaden the spectrum of substrates evaluated in this system, a U-shape reactor was used, and reactions with selected chiral amines were performed.…”