| 摘要 |
<p>1-Alkyl 1,4-dihydro 4-oxo pyridine 3-carboxylic acid deriv. with an aromatic ring condensed in 5,6-position (enoxazine) is made by (a) reducing 2-chloro 3-nitro pyridine with SnCl4 and HCl to the amine; (b) diazotising with C2H5NO2 in fluoboric acid and decomposing the diazonium salt to give 2-chloro 3-fluoro pyridine; (c) heating with piperazine at 140-150 deg. C to give 3-fluoro 2-(1-piperazinyl) pyridine; (d) reacting with NaNH2 in diethylamine to give 2-amino 5-fluoro G-B1; (e) condensing with diethyl ethoxymethylene malonate in silicone oil to give (F); (f) treating with hexamethyl disilazane to give (G); (g) heating with benzene/water in a sealed tube at 160-170 deg. C; (h) treating with C2H5Br to give (H); (i) hydrolysing with NaOH or HCl to give (J) as hydrochloride or acceptable salt. G is C1-D1-4-trimethylsiloxy-E1. C1 is 6-F-7. D1 is 1-piperazinyl. F is C1-D1-4-hydroxy-E. E1 is ethyl 1,8-naphthiridene 3-carboxylate. H is F1-C1-D1-G1-E1. F1 is 1-ethyl. G1 is 1,4-dihydro oxo. J is F1-C1-D1-G1-1,8-naphthiridone 3-carboxylic acid or enoxazine.</p> |
