Su Dong Cho

Alkylthioether synthesis via imidazole mediated mitsunobu condensation

Abstract Unsymmetric alkylthioethers can be prepared from aliphatic thiols and unhindered alcohols under modified Mitsunobu conditions using trimethylphosphine/1,1′-(azodicarbonyl)dipiperdine (ADDP) in the presence of imidazole (2 equivalents).

Synthetic studies on isoquinoline derivatives with multidrug resistance (MDR) modulating activity

Tetrahydropyridazino-1,4-oxazinoisoquinoline derivatives with multidrug resistance (MDR) modulating activity were designed and synthesized. A key step for cyclization of 1,4-oxazine ring was developed using K 2 CO 3 and CH 3 CN in one-pot. Among prepared compounds, 2-(4-fluorobenzyl)-9,10-dimethoxy-12-methyl-6,7,11b,12-tetrahydropyridazino[4,5,5,6][1,4]oxazine-[3,4,-a]isoquinolin-1(2H)-one (lf) exhibited significant MDR reversing activity and low toxicity, which might be as potential MDR agent.

Regioselectivity of Pictet–Spengler cyclization: synthesis of halotetrahydroisoquinolines

Abstract The regioselectivity of the Pictet–Spengler cyclization for the synthesis of isoquinolines depends on the aryl substituent at C-2. The ratio of halotetrahydroisoquinoline 4 to isoquinoline 3 increases with increasing electrophilicity of the aromatic ring (H≪I

One‐Pot Synthesis of Pyridazino[1,4]oxazin‐3‐ones

Abstract Pyridazino[1,4]oxazin‐3‐ones were conveniently prepared in a one‐pot condensation of N‐substituted 2‐chloroacetamides with various 5‐chloro‐pyridazin‐6‐ones via rearrangement of a spiro‐aminoketal intermediate.