Kyoko Nakagawa

Syntheses of (±)-clavicipitic acid and its derivatives

A formal total synthesis of (±)-clavicipitic acid was achieved in five steps from indole-3-carboxaldehyde. Syntheses of (±)-4-cyano-, (±)-4-methyl-, and (±)-4-hydroxymethyl-6-(2-methyl-1-propen-1-yl)- 3,4,5,6-tetrahydro-1H-azepino [5,4,3-cd] indoles are also reported

A simple four step synthesis and optical resolution of 4-nitro-1,3,4,5-tetrahydrobenz[cd]indole, and the synthesis of 1-hydroxy derivatives of 4-nitro- and 4-amino-1,3,4,5-tetrahydrobenz[cd]indole

4-Nitro-1,3,4,5-tetrahydrobenz[cd]indole was synthesized from indole-3-carboxaldehyde in four steps with an overall yield of 30%. Optical resolution of its enantiomers by chiral column chromatography was successful. Syntheses of 1-hydroxy derivatives of 4-nitro- and 4-amino-1,3,4,5-tetrahydrobenz[cd]indoles are also reported

Ergot alkaloids : the first and five step total syntheses of (-)- and (+)-6,7-secoagroclavines, and the syntheses of (-)- and (+)- 6-nor-6-propyl-6,7-secoagroclavines ((-)- and (+)-KSU 1415)

Simple synthetic method for optically active 4,5-trans-((-)- and (+)-6) and 4,5-cis-5-(2-methyl-1-propen-1-yl)-4-nitro-1,3,4,5-tetrahydrobenz[cd]indoles ((-)- and (+)-7) was developed. Using these chiral common synthetic intermediates, the first total syntheses of (-)- and (+)-6,7-secoagroclavines were achieved in only five steps. Preparations of (-)- and (+)-6-nor-6-propyl-6,7-secoagroclavines ((-)- and (+)-KSU 1415) are also described

Syntheses of 4-amino-, 4-hydroxy-, and 4-nitro-1,3,4,5-tetrahydrobenz[cd]indoles and its bromination

Simple synthetic method for 4-nitro-1,3,4,5-tetrahydrobenz[cd]indole (6) is established from indole-3-carboxaldehyde (7). With 6 in hand, various derivatives of 4-amino-, 4-hydroxyand 4-amino-4-hydroxymethyl-1,3,4,5tetrahydrobenz[cd]indoles become readily available. Bromination of 6 afforded useful building blocks for further manipulation. Successful optical resolution of 6 by chiral column chromatography is also reported.