Substituted Tetrahydropyrimidinones: A New Herbicidal Class of Compounds Inducing Chlorosis by Inhibition of Phytoene Desaturation

Interaction of Aquatic Dissolved Organic Matter(DOM) with Amitrole: The Nature of the Bound Residues

“…For 15 N-NMR spectroscopy of DOM-amitrole complexes 500 mg DOM (Hohlohsee) respectively 1 g DOM generated from 15 …”

“…After 8 days the cress tests were photographed and compared visually for specific harmful effects. The shoot systems were lyophilized and extracted with acetone for analyzing the phytoene contents [15].…”

“…The water used was deionized and filtered by a Milli-Q-system (Millipore Corp. Bedford, MA, USA). 15 N-labelled copper(II) nitrate was synthesized by adding 150 µL of concentrated hydrochloric acid and 250 µL of H 2 O 2 (30%) to a mixture of 65 mg of powdered copper, 100 mg of K 15 NO 3 (15% 15 N, Aldrich), and 500 µL of Milli-Q-water. After 30 minutes of reaction additional amounts of 50 µL of concentrated hydrochloric acid and 250 µL of H 2 O 2 (30%) were applied (solution A).…”

Bleaching Herbicides: Action Mechanism in Carotenoid Biosynthesis, Structural Requirements and Engineering of Resistance

“…An overlay of the structures reveals that the keto group in compounds like fluridone can be replaced by the imine groups of various heterocycles (Babczinski et al 1992). Other influences of the conjugated system of the heterocycle seem to be minor since the nonaromatic tetrahydropyrimidinones (Babczinski et al 1995b) and ketomorpholines (Sandmann and Mitchell2001) are also very potent inhibitors of phytoene desaturase. In many bleachers the substituent at the six-membered central ring opposite the keto group or an electronically equivalent N imine (Babczinski et al 1992) is sterically well defined.…”

“…Since then, novel compounds have been identified as phytoene desaturase inhibitors. Among them are 2,6-diphenylpyridines (Kawamura et al 1991;Babczinski et al 1992), diarylpyrimidines (Kawamura et al 1993), tetrahydropyrimidinones (Babczinski et al 1995a), I,l'-biphenyl derivatives (Laber et al 1999), phenylpyrimidinones (Burdge 2000) and diphenylpyrrolidinones (Ogawa et al 2001). Typical and efficient bleaching compounds possess a central five-or sixmembered heterocycle carrying one or two substituted phenyl rings.…”