Herbicidal (2 or 6)-fluoroalkyl-4-amino pyridine derivatives
申请人:Monsanto Company
公开号:US04698093A1
公开(公告)日:1987-10-06
Disclosed herein are 3,5-pyridinedicarboxylic acid derivatives having heteroatom substitution at the 4 position which are useful as herbicides and herbicide precursors.
An efficient and operationally simple synthesis of (±)-thienamycin is described.
描述了(±)-硫霉素的有效且操作简单的合成。
Process for preparation of substituted pyridines
申请人:Monsanto Company
公开号:US04824954A1
公开(公告)日:1989-04-25
Disclosed herein is a novel process for the preparation of 4-amino-3,5-pyridinedicarboxylate derivatives by (a) reaction of an acetonediester with a primary amine to form an enamine, (b) reaction with a carboxylic acid anhydride or halide to form a 2-alkylcarbonyl-3-amino-2-pentenedicarboxylate, and (c) reaction with a halogenated alkylnitrile to form the pyridinedicarboxylate product. The product is useful as a herbicide or an intermediate in the formation of a herbicide.
Disclosed is a process for the stereocontrolled total synthesis of thienamycin, which synthesis proceeds via intermediate II: ##STR1## wherein R is a readily removable carboxyl protecting group; and ##STR2## is a readily removable acyl group.
Disclosed is a process for the stereocontrolled total synthesis of thienamycin, which synthesis proceeds via intermediate II: ##STR1## wherein R.sup.3 is a readily removable carboxyl protecting group.