The introduction of the or-hydroxybutyrate chain on the 4 position of 0-picoline via the 4- lithio derivative gave 7. The oxidation of the 3-methyl substituent required for lactone formation between the substituents on the 3 and 4 positions of 7 to give 14 could only be accomplished after introducing a chloro group adjacent to the ring nitrogen. The quaternisation of 2 and the hydrolysis of the aryl-a-chloro substituent completed the ...
![4-ethyl-4-hydroxy-8-iodo-7-naphthalen-2-ylmethyl-3-oxo-3,4-dihydro-1H-pyrano[3,4-c]pyridinium, iodide Structure](https://image.chemsrc.com/caspic/012/40899-52-3.png)
![1H-Pyrano[3,4-c]pyridine-3,8(4H,7H)-dione,4-ethyl-4-hydroxy-7-(2-naphthalenylmethyl)- Structure](https://image.chemsrc.com/caspic/499/48211-40-1.png)
![2-chloro-7-ethyl-7-hydroxy-9-oxa-3-azabicyclo[4.4.0]deca-2,4,11-trien-8-one Structure](https://image.chemsrc.com/caspic/350/40899-34-1.png)
