RESUMO
Novel aryl chain isosters and analogues of 7-keto-8-aminopelargonic acid (KAPA) and 7,8-diaminopelargonic acid (DAPA), the vitamer intermediates involved in the biosynthetic pathway of biotin, possessing chain lengths of eight carbon atoms, were prepared and evaluated as potential herbicides. In the greenhouse test the most active compounds were the fluorinated derivative 9d and the selenophenyl/furan mixture 17m/17p, which were most active against Foxtail millet. In the more sensitive Arabidopsis test the most active substances were 9a and 17m, which displayed GR(50) (concentration of active compound causing 50% growth inhibition) values of 0.2 and 0.5 mg kg(-1) respectively (values of < 50 mg kg(-1) are considered herbicidal).
Assuntos
Diamino Aminoácidos/química , Aminoácidos/química , Herbicidas/síntese química , Magnoliopsida , Biotina/biossíntese , Conformação MolecularRESUMO
A novel methodology for the evaluation of receptor arrangement in structurally flexible anion chemosensors was developed and applied to map the binding site of a new pseudocyclic tristhiourea chemosensor (6). The syntheses of 6 and related macrocyclic chemosensor 10 (a model of the folded monomeric structure of 6) are reported. Both chemosensors were evaluated by titration with a variety of structurally different anions in CH3Cl and DMSO, showing a common preference for F-, CH3CO2-, and H2PO4-. However, within this group of anions, the binding patterns of the chemosensors differed, indicating dissimilarity in the arrangement of the binding sites of 6 and 10.
Assuntos
Ânions/química , Tioureia/química , Ciclização , Dimerização , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Conformação Molecular , Fotoquímica , TitulometriaRESUMO
Isosteres and analogues of 7-keto-8-aminopelargonic acid (KAPA) and 7,8-diaminopelargonic acid (DAPA), the vitamer intermediates involved in the biosynthetic pathway of biotin, possessing chain lengths of eight carbon atoms, were prepared and evaluated as potential herbicides. The most active compounds, 7-amino-octanoic acid hydrochloride and 7-allyloxy-6-oxo-octanoic acid, displayed Arabidopsis GR50 (concentration of the active compound that causes a 50% growth inhibition) values of 5 and 10 mg kg(-1) respectively. The DAPA analog 6,7-diamino-octanoic acid dihydrochloride, when tested in the greenhouse against six weed species, displayed moderate activity against three species, being most active against foxtail millet.
