127199-41-1

Upstream product

• 129306-05-4 ethyl 1-(2-bromoacetyl)cyclopropanecarboxylate 
• 32933-03-2 ethyl 1-acetylcyclopropanecarboxylate 
• 127199-37-5 4,7-dioxo-5-<1(R)-phenylethyl>-5-azaspiro<2.4>heptane 
• 127199-38-6 7-(S)-amino-5-<1(R)-phenylethyl>-4-oxo-5-azaspiro<2.4>heptane 

Downstream Products

• 127199-42-2 7(S)-<(tert-butoxycarbonyl)amino>-5-<1(R)-phenylethyl>-5-azaspiro<2.4>heptane 
• 127199-06-8 7-((S)-7-Amino-5-aza-spiro[2.4]hept-5-yl)-8-chloro-6-fluoro-1-((1S,2R)-2-fluoro-cyclopropyl)-4-oxo-1,4-dihydro-quinoline-3-carboxylic acid 
• 127254-12-0 sitafloxacin 
• 127199-06-8 7-((S)-7-Amino-5-aza-spiro[2.4]hept-5-yl)-8-chloro-6-fluoro-1-(2-fluoro-cyclopropyl)-4-oxo-1,4-dihydro-quinoline-3-carboxylic acid 
• 127199-45-5 (7S)-5-azaspiro[2.4]heptan-7-ylcarbamic acid tert-butyl ester 

Relevant academic research and scientific papers

Preparation method of sitafloxacin hydrate five-membered ring side chain intermediate

The invention relates to a preparation method of a sitafloxacin hydrate five-membered ring side chain intermediate. The preparation method comprises following steps: keto carbonyl groups of a raw material 1 are reacted with sodium cyanoborohydride or sodium triacetoxyborohydride in the presence of ammonium acetate or ammonium chloride; reduction of amide carbonyl groups of an obtained production is realized with lithium aluminum hydride; free amino groups of a reduction product are reacted with di-tert-butyl dicarbonate ester in the presence of an alkali; phenethyl groups of an obtained compound are subjected to reductive destruction with formic acid or a formate in the presence of palladium-carbon so as to obtain the sitafloxacin hydrate intermediate (product 5). Reaction conditions of the preparation method are mild; equipment requirements are low; preparation process is safe; stereoselectivity is excellent; the raw material reagents are cheap and easily available; and production cost is low.

(Fluorocyclopropyl)quinolones. 2. Synthesis and stereochemical structure- activity relationships of chiral 7-(7-amino-5-azaspiro[2.4]heptan-5-yl)-1- (2-fluorocyclopropyl)quinolone antibacterial agents

A series of novel chiral 7-(7-amino-5-azaspiro[2.4]heptan-5-yl)-8-chloro- 1-(2-fluorocyclopropyl)-quinolones were synthesized as a continuation of a research project of 1-(2-fluorocyclopropyl)-quinolones by considering stereochemical and physicochemical properties of the molecule. Absolute configurations of the 1-(cis-2-fluorocyclopropyl) moiety and the 7-(7-amino- 5-azaspiro-[2.4]heptan-5-yl) moiety were determined by X-ray crystallographic analysis. Stereochemical structure-activity relationship studies indicated that 1-[(1R,2S)-2-fluorocyclopropyl] and 7-[(7S)-amino-5-azaspiro[2.4]heptan- 5-yl] derivatives are more potent against Gram-positive and Gram-negative bacteria than the other stereoisomers and 7-[(7S)-7-amino-5-azaspiro[2.4]- heptan-5-yl]-8-chloro-1-[(1R,2S)-2-fluorocyclopropyl]quinolone (33) is the most potent of all stereoisomers. Pharmacokinetic profiles and physicochemical properties of the selected compounds were also examined, and it was found that 33 (DU-6859a) possesses moderate lipophilicity and good pharmacokinetic profiles.