478946-91-7

Upstream product

• 29681-38-7 methyl 5-methylpyridine-2-carboxylate 
• 401792-84-5 methyl 5-(bromomethyl)-6-methoxy-2-pyridinecarboxylate 
• 401792-87-8 methyl 5-formyl-6-methoxy-2-pyridinecarboxylate 
• 401792-82-3 methyl 6-methoxy-5-methyl-2-pyridinecarboxylate 
• 401792-80-1 methyl 6-hydroxy-5-methyl-2-pyridinecarboxylate 
• 401792-77-6 methyl 5-methyl-2-pyridinecarboxylate N-oxide 
• 589-93-5 2,5-dimethylpyridine 
• 401792-93-6 (+)-methyl N-(benzyloxycarbonyl)-3-[2-(methoxycarbonyl)-6-methoxy-5-pyridinyl]-L-alaninate 

Relevant academic research and scientific papers

Nonproteinogenic amino acids: An efficient asymmetric synthesis of (S)-(-)-acromelobic acid and (S)-(-)-acromelobinic acid

An efficient synthesis of (S)-(-)-acromelobic acid (1) and (S)-(-)-acromelobinic acid (2) is described via asymmetric hydrogenation protocol. Asymmetric hydrogenation of dehydroamino acid derivative 23 using (R,R)-[Rh(DIPAMP)(COD)]BF4 catalyst followed by removal of the protective groups afforded (S)-(-)-acromelobic acid (1) in >98% ee. The key intermediate 23 was prepared from citrazinic acid (8). The dehydroamino acid derivative 33 required for the synthesis of (S)-(-)-2 was prepared from 2,5-lutidine (27), which upon hydrogenation using (S,S)-[Rh(Et-DuPHOS)(COD)]BF4 catalyst afforded (S)-(+)-34 in 93% yield and >96% ee. Removal of protective groups in (S)-(+)-34 afforded (S)-(-)-acromelobinic acid (2) in good overall yield.

Asymmetric synthesis of (S)-(-)-acromelobinic acid

A total synthesis of (S)-(-)-acromelobinic acid 2, which was isolated from clitocybe acromelalga, was achieved via an asymmetric hydrogenation protocol. Dehydroamino acid derivative 12 was prepared from 2,5-lutidine 5 and subjected to asymmetric hydrogenation using (S,S)-[Rh(Et-DuPHOS)(COD)]BF4 to give the (S)-(+)-pyridylalanine derivative 13 in 93% yield and >96% e.e. Removal of the protecting groups in (S)-(+)-13 afforded (S)-(-)-acromelobinic acid 2.