Table 1.

Reaction conditions for the preparation of berberine derivative 3 (1 equivalent of substrate, no base used).

Reaction	DBP (Equivalents)	Solvent	Temperature (°C)	Time (h)	Yield (%)
R1	3	CH3CN	60	2	48
R2	10	CH3CN	60	2	55
R3	10	DMF	80	2	59
R4	58	DMF	80	2	74