Mimics of transaminase enzymes

Abstract

1969with an OLIS 3820 Data System for data collection, storage, and analysis. and, after stabilization at -20 'C, their "P spectra.Methods. The 3'P('H) NMR spectra were recorded at 121.5 MHz on a Bruker WM 300 spectrometer with appropriate temperature control for spectra recorded below ambient temperature. Splitting patterns were NT-300 spectrometer. The latter instrument was also used for routine 'H spectra. UV-vis spectra and the kinetics measurements in the slower reactions were measured on a Cary Model 219 spectrophotometer. Kinetic data were fit to suitable equations by standard least-squares programs. More rapid reactions were monitored at suitable wavelengths on a Canterbury Model SF-3A stopped-flow spectrophotometer interfaced Acknowledgment.Abstract: Pyridoxamine has been attached to the primary side and to the secondary side of P-cyclodextrin; the resulting compounds convert a-keto acids to amino acids with substrate selectivity and some stereoselectivity. Pyridoxamine has also been attached to a synthetic macrocycle; the attached binding group showed substrate selectivity. Chains carrying catalytic basic groups have been attached to pyridoxamine; appropriate systems catalyze the prototropic rearrangement characteristic of transamination. A catalyzed HCI elimination involving chloropyruvic acid was also observed. A tetrahydrcquinoline system related to pyridoxamine was synthesized to permit the stereochemically defined placement of a basic catalytic group. This converted keto acids to amino acids with good stereoselectivity for the formation of optically active products.( I ) NIH postdoctoral fellow, 1981-1983.

Cyclodextrin-based enzyme models. Part 1. Synthesis of a tosylate and an epoxide derived from heptakis(6-O-tert-butyldimethylsilyl)-β-cyclodextrin and their characterization using 2D NMR techniques. An improved route to cyclodextrins functionalized on the secondary face

“…However, in contrast to functionalization of the primary face of cyclodextrins, which has been extensively studied, the chemistry available for functionalization of the secondary face is less well developed. Preparative methods for secondaryfunctionalized cyclodextrins generally involve moderate yields and purification of synthetic intermediates by reverse-phase chromatography, which is scale-limited (5)(6)(7)(8).…”

Enantioselective Transfer Hydrogenation of Aliphatic Ketones Catalyzed by Ruthenium Complexes Linked to the Secondary Face of β‐Cyclodextrin

“…In contrast, modification of the secondary face has been less favoured in the past. [17] Based on a recent X-ray structure of a b-cyclodextrin derivative we believed, however, that it would be possible through secondary face-modification of one sugar unit to change the size and shape of the cavity of b-cyclodextrin. [18] It was anticipated that this would create distinctive features of the corresponding ruthenium complex suitable for the enantioface selective reduction of aliphatic ketones.…”

Synthesis of New Carnosine Derivatives ofβ-Cyclodextrin and Their Hydroxyl Radical Scavenger Ability

“…Derivative 2 has a primary amino group, and the antiglycating activity reported for bAH may be maintained [41]. Derivatives 1 and 3 were synthesized by methods reported in the literature [44] [45]. Compound 2 was synthesized as described for the Boc derivative [46], removing the Boc group.…”