Synthesis and biological activity of enantiomeric pairs of phosphosulfonate herbicides.
The phosphosulfonates are a new class of soil-active herbicides which control a variety of annual grass and broadleaf weeds. Chirality at the phosphorus atom afforded the opportunity to explore stereospecific requirements for herbicidal activity. Chiral (hydroxymethyl)phosphinate intermediates were enzymatically resolved (Pseudomonas fluorescens lipase) from the racemic mixtures and then used to prepare two pairs of enantiomeric phosphosulfonates. Biological testing of the enantiomeric phosphosulfonate herbicides demonstrated that, in each case, the herbicidal activity was attributed to the (+) enantiomer and that the (+) enantiomer is more active than the racemate.
Spangler
L A
LA
Agricultural Products Research, Rohm and Haas Company, 727 Norristown Road, Spring House, Pennsylvania 19477, USA. rselas@rohmhaas.com
Mikolajczyk
M
M
Burdge
E L
EL
Kielbasiński
P
P
Smith
H C
HC
Lyzwa
P
P
Fisher
J D
JD
Omelańczuk
J
J
D006540:Herbicides / Q000138:chemical synthesis; D009943:Organophosphorus Compounds / Q000737:chemistry; D013237:Stereoisomerism; D013451:Sulfonic Acids / Q000138:chemical synthesis / Q000737:chemistry
D006540:Herbicides; D009943:Organophosphorus Compounds; D013451:Sulfonic Acids