Synthesis and application of new 3-amino-2-pyridone based luminescent dyes for ELISA

A Rearrangement of 4-Phenylbenzo[d]oxazoles to Phenanthridin-4-ols

“…Previously, starting from 3-amino-4-phenylpyridine-2(1 H )-ones 11 , 13 we have developed two methods for the synthesis of benzo[ c ][1,7]naphthyridine-4(3 H )-ones 13 , 14 which are precursors of luminescent dyes. 15 One of them was the Pictet–Spengler reaction of 3-amino-4-phenylpyridine-2(1 H )-ones 11 with aromatic aldehydes when heated in phosphoric acid to 130 °C (Scheme 2 ). 14a Severe reaction conditions did not allow the use of aliphatic aldehydes and acid-sensitive compounds.…”

New Synthesis of Pyrazolo[3,4-b]pyridine Derivatives Based on 5-Aminopyrazole and Azlactones

“…As we previously reported, 7-aryloxazolo[5,4- b ]pyridines or 4-phenylbenzo[ d ]oxazoles are capable of rearrangement into benzo[ c ][1,7]naphthyridin-4(3 H )-ones or phenanthridin-4-ols when reacted with aluminum chloride. 3a 12 Oxazolo[5,4- b ]pyridine derivatives annulated at C(5)-C(6) position were not introduced into this reaction. We have found that heating oxazolo[5,4- b ]pyrazolo[4,3- e ]pyridines 5a – c , f – i in chlorobenzene to 130 °C with a two-fold excess of anhydrous AlCl 3 leads to the formation of previously unknown benzo[ c ]pyrazolo[4,3- f ][1,7]naphthyridin-5-ones 7a – c , f , g , pyrazolo[4,3- f ]thieno[3,2- c ][1,7]naphthyridin-6-one 7h or furo[3,2- c ]pyrazolo[4,3- f ][1,7]naphthyridin-6-one 7i in yields of 42–82% (Scheme 3 ).…”

Synthesis of 3‐Aminopyrido[2,1‐a]isoquinolin‐4‐one Derivatives via Condensation of Azlactones with 1‐Alkyl‐3,4‐dihydroisoquinolines

“…In clinical practice, 5‐amino‐[3,4′‐bipyridin]‐6(1 H )‐one 4 , known as the cardiotonic drug Amrinone, is used [17] . In addition, 3‐aminopyridin‐2(1 H )‐ones are used in the synthesis more complex biologically active compounds [18a–m] …”