## Abstract We have developed a stereospecific biosynthesis of ^13^C‐ and ^15^N‐labeled L‐serine which involves the serine‐type methylotroph __Methylobacterium extorquens__ AM1. In this biosynthesis, C‐3 of serine is derived from methanol while C‐2, C‐1 and the α‐amino group are derived from glycin
Enantioselective synthesis of isotopically labelled L-α-amino acids preparation of 13C-, 18O-and 2H-labelled L-serines and L-threonines
✍ Scribed by W. F. J. Karstens; H. J. F. F. Berger; E. R. Van Haren; J. Lugtenburg; J. Raap
- Publisher
- John Wiley and Sons
- Year
- 1995
- Tongue
- French
- Weight
- 815 KB
- Volume
- 36
- Category
- Article
- ISSN
- 0022-2135
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✦ Synopsis
Abstract
[3‐^18^O]‐L‐serine, [3‐^13^C]‐L‐serine, [3‐^18^O]‐L‐threonine, [3,4‐^13^C~2~]‐L‐threonine and [3‐^2^H]‐L‐threonine are prepared from simple commercially available, isotopically enriched starting materials like H~2~^18^O, [^13^C]‐paraformaldehyde, [^13^C~2~]‐acetaldehyde and [1‐^2^H]‐acetaldehyde. The introduction of the side chain is based on the reaction of the anion of the bislactimether of cyclo‐(D‐Val‐Gly) with a suitable reagent. For serine this is isotopically labelled benzylchloromethylether, whereas for threonine labelled acetaldehyde is used in combination with chlorotitaniumtris[diethylamide], introducing both stereocentres in one single step. The isotopomers of serine and threonine are obtained on the gram scale in good yields and high enantiomeric and diasteriomeric excesses. New syntheses for [^18^O]‐benzylalcohol and isotopically enriched benzylchloromethylether are reported. Following the presented synthetic scheme these amino acids can be labelled at any position or at any combination of positions.
📜 SIMILAR VOLUMES
## Abstract Tryptophan synthase catalyzes the nucleophilic replacement of the hydroxyl group at C‐3 of L‐serine. This enzyme can use benzyl mercaptan as a nucleophile in the conversion of serine to S‐benzyl‐L‐cysteine which is deblocked by treatment with sodium in liquid ammonia to yield L‐cysteine
## Abstract We have developed methods for the preparation of L‐glutamic acid, isotopically labeled with ^13^C, using commercially available purified enzymes. The procedure is sufficiently versatile that L‐glutamic acid may be labeled at any carbons or any combination of carbons using ^13^C‐labeled
## Abstract We have developed a stereoselective route to isotopically labeled L‐aspartic acid using L‐serine as a chiral precursor. Labeled serine, prepared biosynthetically was N‐protected by conversion to the N‐__t__‐Boc derivative. (N‐__t__‐Boc)‐[3−^13^C]Serine is cyclized to its β‐lactone which
## Abstract We have developed a stereospecific chemomicrobiological synthesis of labeled tryptophan. L‐[3‐^13^C]Serine, [1‐^15^N]‐ and [2‐^13^C]indole were used as precursors for the synthesis of L‐[β‐^13^C]‐, L‐[1′‐^15^N]‐, and L‐[2′‐^13^C]tryptophan, respectively. The labeled precursors were inco
## Abstract An efficient approach to the enantioselective synthesis of a series of amino acids from either bromoacetyl bromide or glycine is described using a [2,3]‐sigmatropic rearrangement to establish the stereogenic centre at C‐2 under mild conditions. Protected allylglycine **5** is a valuable