Efficient construction of the kedarcidin chromophore ansamacrolide.
[Structure: see text] The streamlined assembly of the ansamacrolide framework of the kedarcidin chromophore via an efficient atropselective Sonogashira coupling step is described. To this end, two newly improved practical syntheses of the cyclopentene and diyne fragments have been developed, which feature 0.2 mol % catalytic loadings for an RCM step and i-PrMgCl/CH2I2 as a new entry to gem-disubstituted epoxides from ketones, both being applicable to 49-g scales.
Koyama
Yasuhito
Y
Department of Chemistry, Graduate School of Science, Tohoku University, COE, Sendai 980-8578, Japan.
Lear
Martin J
MJ
Yoshimura
Fumihiko
F
Ohashi
Isao
I
Mashimo
Tomoko
T
Hirama
Masahiro
M
D000475:Alkenes / Q000138:chemical synthesis / Q000737:chemistry; D000480:Alkynes / Q000138:chemical synthesis* / Q000737:chemistry; D003500:Cyclization; D003516:Cycloparaffins / Q000138:chemical synthesis* / Q000737:chemistry; D053281:Enediynes; D047029:Lactams, Macrocyclic / Q000138:chemical synthesis* / Q000737:chemistry; D018942:Macrolides / Q000138:chemical synthesis* / Q000737:chemistry; D015394:Molecular Structure; D009281:Naphthalenes / Q000138:chemical synthesis* / Q000737:chemistry
D000475:Alkenes; D000480:Alkynes; D003516:Cycloparaffins; D053281:Enediynes; D047029:Lactams, Macrocyclic; D018942:Macrolides; D009281:Naphthalenes; C080542:kedarcidin chromophore