80082-48-0

Upstream product

• 72-19-5 L-threonine 
• 24424-99-5 di-tert-butyl dicarbonate 
• 49705-99-9 (2S,3R)-2-amino-3-hydroxybutanamide 
• 60538-19-4 N-(tert-butoxycarbonyl)-l-threonine methyl ester 
• 2592-18-9 Boc-Thr-OH 

Relevant academic research and scientific papers

Synthesis method of aztreonam monocyclic mother nucleus

The invention discloses a synthesis method of an aztreonam monocyclic mother nucleus, and mainly relates to the technical field of pharmaceutical and chemical industry. The method comprises the stepsthat L-threonine is subjected to methyl esterification; terbutyloxycarbonyl anhydride is used for performing amino BOC protection; ammonia water is subjected to ammonolysis; under the catalysis of a solid basic catalyst, methyl-sulfuric-acyl reaction and sulfonation are performed; cyclization, deprotection and acidification are performed to obtain the aztreonam monocyclic mother nucleus. The raw materials are cheap and can be easily obtained; the yield is high; the cost is low; the synthesis method belongs to a green, energy-saving and environment-friendly practical technology.

Synthesis of the 'northern-hemisphere' fragments of the thiopeptide antibiotic nosiheptide

The northern-hemisphere fragments 4 and 5 of the thiopeptide antibiotic nosiheptide have been synthesized from Boc-Glu-OBn 7 and Boc-Thr 12 in 21.8% and 16.8% overall yields, respectively. Georg Thieme Verlag Stuttgart.

An efficient procedure for the preparation of 4-substituted 5-aminoimidazoles

The preparation of O-methylimidates from α-aminonitriles and their subsequent co-cyclization with primary amines to afford 4-substituted 5-aminoimidazoles was studied. It was found that the mildly acidic pyridinium p-toluenesulfonate efficiently catalyzed each stage of the reaction sequence: (a) the formation of the O-methylimidates, (b) their co-cyclization with a variety of primary amines, and (c) certain derivatizations of the resultant heterocycles. The developed reaction conditions tolerate a wide variety of α-aminonitriles and primary amine co-reactants. Thus, it is possible to easily prepare a diverse array of substituted heterocyclic compounds in good yield. The requisite α-aminonitriles were synthesized either from amino acids or by phase-transfer alkylation of a glycine anion equivalent. The unstable free 5-aminoimidazoles were normally protected in situ to provide derivatives (methyl imidates or N,N-dimethylamidines) that were amenable to characterization.

Dichlorotris(dimethylamino)phosphorane as a Dehydratisation Reagent for the Preparation of N-Protected Amino Acid Amides

Besides for the synthesis of peptides and activated esters dichlorotris(dimethylamino)phosphorane (2) now proved to be an excellent reagent for the preparation of N-protected amino acid amides.

4-alkylated monobactams. Chiral synthesis and antibacterial activity

The synthesis of 4-alkylated monobactams by a variety of procedures is described. Two complementary procedures have been developed for the chiral synthesis of monobactams: (1) sulfonation of 4-alkyl-3-(protected)amino-2-azetidinones with various complexes of SO3; and (2) cyclization of β-mesyloxyacyl sulfamates derived from β-alkyl-β-hydroxy-α-amino acids. The most general procedure involves introduction of the alkyl group via a Grignard reaction on 6-APA-derived sulfones 23 or 24 followed by sulfonation. For the specific case of (3S,trans-)-3-amino-4-methylmonobactamic acid (48), cyclization of the β-mesyloxyacyl sulfamate 40 derived from (L)-threonine is the preferred route. The introduction of 4-alkyl groups into monobactams results in a decrease in activity against gram-positive bacteria, an increase in activity against gram-negative bacteria, and an increase in β-lactamase stability. Increasing the size of the alkyl group beyond methyl results in diminished intrinsic antibacterial activity. 4β-Alkylmonobactams display better β-lactamase stability than their 4α-counterparts.

Monobactams. Stereospecific Synthesis of (S)-3-Amino-2-oxoazetidine-1-sulfonic Acids

A facile, stereospecific synthesis of 3-amino-2-oxoazetidine-1-sulfonic acids (monobactams) by the cyclization of acyl sulfamates derived from β-hydroxy amino acids is described.