Preparation and Photosynthesis-Inhibiting Activity of 1-[(2-Nitrophenyl)carbamoyl]naphthalen-2-yl Alkylcarbamates
Proceedings of The 20th International Electronic Conference on Synthetic Organic Chemistry
In this study, a series of eight 1-[(2-nitrophenyl)carbamoyl]naphthalen-2-yl alkylcarbamates was prepared and characterized. The discussed compounds were prepared by microwave-assisted and conventional synthesis. The compounds were tested for their activity related to inhibition of photosynthetic electron transport (PET) in spinach (Spinacia oleracea L.) chloroplasts. The PET-inhibiting activity of the compounds was relatively low; the corresponding IC 50 values ranged from 0.233 to 0.487
... and the highest activity within the series of compounds was observed for 1-[(2-nitrophenyl)carbamoyl]naphthalen-2-yl pentylcarbamate. The compounds were found to inhibit PET in photosystem II. Study of photosynthetic electron transport (PET) inhibition in spinach chloroplasts Chloroplasts were prepared from spinach (Spinacia oleracea L.) according to Masarovicova and Kralova . The inhibition of photosynthetic electron transport (PET) in spinach chloroplasts was determined spectrophotometrically (Genesys 6, Thermo Scientific), using the artificial electron acceptor 2,6-dichlorophenol-indophenol (DCPIP) according to Kralova et al. , and the rate of photosynthetic electron transport was monitored as a photoreduction of DCPIP. The measurements were carried out in phosphate buffer (0.02 mol/L, pH 7.2) containing sucrose (0.4 mol/L), MgCl 2 (0.005 mol/L) and NaCl (0.015 mol/L). The chlorophyll content was 30 mg/L in these experiments, and the samples were irradiated (~100 W/m 2 with 10 cm distance) with a halogen lamp (250 W) using a 4 cm water filter to prevent warming of the samples (suspension temperature 4 °C). The studied compounds were dissolved in DMSO due to their limited water solubility. The applied DMSO concentration (up to 4%) did not affect the photochemical activity in spinach chloroplasts. The inhibitory efficiency of the studied compounds was expressed by IC 50 values, i.e. by molar concentration of the compounds causing a 50% decrease in the oxygen evolution rate relative to the untreated control. The comparable IC 50 value for the selective herbicide 3-(3,4-dichlorophenyl)-1,1-dimethylurea, DCMU (Diuron ® ), was about 0.002 mmol/L. The results are summarized in Table 1.