Table 1.

NMR Spectroscopic Data for Pyridinopyrone A (1) (600 MHz for ¹H, 150 MHz for ¹³C (acetone-d₆)^a

C #	δC	δH mult (J in Hz)	HMBC b
1	162.4, C
2	88.3, CH	5.51, s	1, 3, 4
3	170.9, C
4	100.7, CH	6.08, s	2, 3, 5, 6
5	158.8, C
6	122.5, CH	6.35, d (15.0)	4, 5, 7, 8
7	135.6, CH	7.15, dd (15.0, 11.0)	5, 6, 8, 9
8	127.8, CH	6.61, dd (15.0, 11.0)	6, 7, 10
9	142.6, CH	6.81, d (15.0)	7, 10, 11, 10-CH3
10	137.0, C
11	135.3, CH	6.55, d (10.9)	9, 12, 13, 10-CH3
12	128.2, CH	7.47, dd (15.6, 10.9)	10, 11, 13, 3'
13	129.1, CH	6.78, d (15.6)	11, 2', 4'
2'	145.3, CH	8.72, s	13, 4', 6'
3'	134.1, C
4'	132.6, CH	8.01, d (7.8)	13, 2', 6'
5'	122.8, CH	7.35, dd (7.8, 4.8)	3', 6'
6'	145.2, CH	8.44, d (4.8)	2', 4', 5'
3-OMe	55.7, CH3	3.89, s	3
10-Me	12.0, CH3	2.07, s	9, 10, 11

^aAssignments made by interpretation of COSY,HSQC and HMBC NMR data.

^bHMBC correlations are from the proton(s) stated to the indicated carbon.