Ring-substituted 4-Hydroxy-1H-quinolin-2-ones: Preparation and Biological Activity

Abstract

In the study, a series of twelve ring-substituted 4-hydroxy-1H-quinolin-2-one derivatives were prepared. The procedures for synthesis of the compounds are presented. The compounds were analyzed using RP-HPLC to determine lipophilicity and tested for their photosynthesis-inhibiting activity using spinach (Spinacia oleracea L.) chloroplasts. All the synthesized compounds were also evaluated for antifungal activity using in vitro screening with eight fungal strains. For all the compounds, the relationships between the lipophilicity and the chemical structure of the studied compounds are discussed, as well as their structure-activity relationships (SAR).

Synthesis of some novel oxazolopyranoquinolinones from 3-amino-4‐hydroxypyrano[3,2-c]quinolindione

“…Attempts to reduce the nitro compound 2 using activated iron 21 or FeCl3/Zn/DMF/H2O, 22 were not effective; a mixture of products was isolated, which could not be separated in a satisfactory manner to obtain any considerable amount of the amino derivative. Instead, we used tin, as previously described by Jampilek 23 in th e syn the si s o f 4-hydroxy-3-nitroquinolin-2-one. Accordingly, the nitro-derivative 2 was reduced with tin and concentrated hydrochloric acid at 130 °C to produce 3-amino pyrano[3,2-c]quinoline-2,5-dione 3 in 70% yield (Scheme 1).…”

Photosynthetic Inhibitors

“…Considering the quinolines (31), no simple structure-activity relationship explaining the observed activity was found being the two most active derivatives (31a) and (31b) (Musiol et al, 2008). In a series of twelve ring-substituted 4-hydroxy-1H-quinolin-2-one derivatives (general structure 32), all of the compounds displayed very low inhibitory activity (IC 50 ranging from 126 to 925 mol L -1 ) on electron transport in photosynthesis from water to DCPIP (Jampilek et al, 2009a). The best activities were observed with derivatives (32a) and (32b).…”

Preparation and Herbicidal Activity of Halogenated 8-Hydroxyquinoline-2-carboxanilides

“…In addition, according to the results reported recently, some quinoline derivatives and their analogues/isosteres also showed noteworthy herbicidal activities [7][8][9][10][11][12][13][14][15][16][17][18][19][20]. Although at present approximately 20 mechanisms of action of herbicides are known [21], over 50% of commercially available herbicides act by reversible binding to photosystem II (PS II), a membrane-protein complex in the thylakoid membranes, which catalyses the oxidation of water and the reduction of plastoquinone [22], and thereby inhibit photosynthesis [23][24][25].…”

“…Although at present approximately 20 mechanisms of action of herbicides are known [21], over 50% of commercially available herbicides act by reversible binding to photosystem II (PS II), a membrane-protein complex in the thylakoid membranes, which catalyses the oxidation of water and the reduction of plastoquinone [22], and thereby inhibit photosynthesis [23][24][25]. Some organic compounds, possessing an amide (-NHCO-) group, e.g., substituted anilides [11,[15][16][17][18]20], or a wide variety of compounds containing the quinoline system [9,10,[12][13][14]19] were found to interact with tyrosine radicals Tyr Z and Tyr D (or their surroundings) which are situated in D 1 and D 2 proteins on the donor side of PS II. Due to this interaction, interruption of the photosynthetic electron transport occurs.…”

“…Due to this interaction, interruption of the photosynthetic electron transport occurs. In the context of the previously-described azanaphtalenes and their isosteres [7][8][9][10][11][12][13][14][15][16][17][18][19][20], new simple modifications of quinoline that can possess interesting biological activity were investigated. The compounds were tested for their photosynthesis-inhibiting activity -the inhibition of photosynthetic electron transport in spinach chloroplasts (Spinacia oleracea L.).…”