Abstract
5-Amino-4-formyl pyrazole 1 was used as a precursor for the synthesis of 6-
aminopyrazolo[3,4-b]pyridine-5-carbonitrile 2, and 6-aminopyrazolo[3,4-b]pyridine-5-
carboxamides 3 and 4. Pyrazolo[3,4-b]pyridines 2, 3, and 4 were treated with different reagents
leading to structurally confirmed heterocycles. Mosquito adult females carry and
transmit the causatives of many diseases to humans and other domestic animals. Therefore,
their management has become a necessity. Ten of the synthesized compounds were tested for
larvicidal activity against second-stage C. pipiens larvae.
IR spectra were recorded on Shimadzu-408 infrared spectrophotometer. The NMR spectra
were performed on a Bruker AV-400 spectrometer and JEOL ECA II 500 MHz. Mass spectrometry
was provided on a Varian MAT 312 instrument in EI mode (70 eV). Lethal concentrations
were calculated based on probit analysis. Biochemical enzymes were analyzed using analysis of variance
ANOVA with Graph Pad Prism 5. Mean comparisons were analyzed using Tukey's test.
Five compounds, 1, 2, 4, 5 and 11 exhibited detectable insecticidal activity as these compounds recorded 154.4,
5.6x103, 8.4, 135.1 and 697.2 ppm, respectively. Moreover, the effect of these insecticidal compounds on lipids and
carbohydrates digestive pathways in the larvae was evaluated by comparing the activities of amylase and lipase
digestive enzymes in both control and treated larvae. Compounds 1, 4 and 5 showed an inhibitory effect on both
lipase and amylase enzymes. Compound 2 inhibited lipase activity, while compound 11 didn’t affect both enzymes
compared with the control.
Results showed that the incorporation of pyridine and pyrazole induced significant insecticidal activity against larval
mosquitoes. Furthermore, insertion of amino or carbonyl groups into the synthesized compounds enhanced the
insecticidal activity. Our findings showed that development of such novel compounds is promising in enhancing the
agricultural productivity and management of diseases transmitted by insects.
Graphical Abstract
[10]
a) Abdu-Allah, H.H.M.; El-Emary, T.I. Synthesis and preliminary biological screening of 6-aminopyrazolo[3,4-b]pyridine derivatives.
Pharma Chem., 2016,
8, 9-16.;
b) El-Emary, T.I. Synthesis of newly substituted pyrazoles and substituted pyrazolo[3,4-b]pyridines based on 5-amino-3-methyl-1-phenylpyrazole.
J. Chin. Chem. Soc., 2007,
54(2), 507-518.
[
http://dx.doi.org/10.1002/jccs.200700072];
c) el-Emary, T.I.; Hussein, A.M.; el-Kashef, H.S. New polycyclic azines derived from pyrazolo[3,4-b]pyridine.
Pharmazie, 2000,
55(5), 356-358.
[PMID:
11828614];
d) El-Emary, T.I. A convenient synthetic approach to newly condensed pyrazolo-azines based on pyrazolo[3,4-b]pyridine.
J. Chin. Chem. Soc., 1999,
46(4), 585-590.
[
http://dx.doi.org/10.1002/jccs.199900080];
e) El-Emary, T.; El-Mohsen, S. Multi-component one-pot synthesis and antimicrobial activities of 3-methyl-1,4-diphenyl-7-thioxo-4,6,8,9-tetrahydro-pyrazolo[5,4-b]pyrimidino[5,4-e]pyridine-5-one and related derivatives.
Molecules, 2012,
17(12), 14464-14483.
[
http://dx.doi.org/10.3390/molecules171214464] [PMID:
23222865];
f) Abdelmohsen, S.A.; Emary, T.I.E. Synthesis, characterization and antimicrobial activity of novel pyrazolo[3,4-b]pyridines and their spiro-heterocyclic derivatives.
J. Adv. Chem, 2014,
10(7), 2901-2915.
[
http://dx.doi.org/10.24297/jac.v10i7.6802];
g) Aly, A.A.; El-Emary, T.I.; Mourad, A.F.E.; Alyan, Z.K.; Bräse, S.; Nieger, M. Synthesis of new heterocycles from reactions of 1-phenyl-1H-pyrazolo[3,4-b]pyridine-5-carbonyl azides.
J. Heterocycl. Chem., 2019,
56(4), 1369-1375.
[
http://dx.doi.org/10.1002/jhet.3511];
h) Aly, A.A.; El-Emary, T.I.; Mourad, A.F.E.; Khallaf Alyan, Z.; Bräse, S.; Nieger, M. 5-Carbohydrazide and 5-carbonylazide of pyrazolo[3,4- b]pyridines as reactive intermediates in the synthesis of various heterocyclic derivatives.
J. Chem. Res., 2019,
43(7-8), 219-229.
[
http://dx.doi.org/10.1177/1747519819861625]
[17]
Saggar, S.; Sisko, J.; Tucker, T.; Tynebor, R.; Su, D.; Anthony, N.U.S. Acoustic alert communication system with enhanced signal to noise. Chem. Abstr., 2007, 146, 163149.
[26]
Feurer, A.; Luithle, J.; Wirtz, S.; Koenig, G.; Stasch, J.; Stahl, E.; Schreiber, R.; Wunder, F.; Lang, D. PCT Intl. Appl. WO 2004009589. Chem. Abstr., 2004, 140, 146157.
[32]
a) Youssef, M.S.K.; Abeed, A.A.O. Synthesis, characterization and pharmacological activities of pyrimidine derivatives containing 2-pyrazolin-5-one.
Int. J. Pharm., 2014,
5, 1705-1720.;
b) Youssef, M.S.K.; Omar, A.A. Synthesis and Reactions of 5-Amino-3-(3-methyl-5-oxo-1-phenyl-2-pyrazolin-4-yl)-7-phenyl-7H-thiazolo[3,2-a]pyrimidine-6-carbonitrile.
Monatsh. Chem., 2007,
138(10), 989-995.
[
http://dx.doi.org/10.1007/s00706-007-0703-5];
c) Youssef, M.S.K.; Abbady, M.S.; Ahmed, R.A.; Omar, A.A. Synthesis of some new heterocycles derived from ethyl 7-amino-3-(3-methyl-5-oxo-1-phenyl-2-pyrazolin-4-yl)-5-aryl-5H-thiazolo[3,2-a]pyrimidine-6-carboxylate of Biological Importance.
J. Heterocycl. Chem., 2013,
50(2), 179-187.
[
http://dx.doi.org/10.1002/jhet.735];
d) Youssef, M.S.K.; Abbady, M.S.; Ahmed, R.A.; Omar, A.A. Preparation and Reactions of 2-Methyl-7-(3-methyl-5-oxo-1-phenyl-2-pyrazolin-4-yl)-5-arylthiazolo[3,2-a]-pyrimido[4,5-d]oxazin-4(5H)-one.
Chin. J. Chem., 2011,
29(7), 1473-1482.
[
http://dx.doi.org/10.1002/cjoc.201180268];
e) Abeed, A.A.O.; Youssef, M.S.K.; Hegazy, R. Synthesis, anti-diabetic and renoprotect-ive activity of some new benzazole, thiazolidin-4-one and azetidin-2-one derivatives.
J. Braz. Chem. Soc., 2017,
28, 2054-2063.;
f) Youssef, M.S.K.; Abeed, A.A.O.; El-Emary, T.I. Synthesis and evaluation of chromene-based compounds containing pyrazole moiety as antimicrobial agents.
Heterocycl. Commun., 2017,
23(1), 55-64.
[
http://dx.doi.org/10.1515/hc-2016-0136];
g) Abeed, A.A.O.; Jaleel, G.A.A.; Youssef, M.S.K. Novel heterocyclic hybrids based on 2-pyrazoline: Synthesis and assessment of anti-inflammatory and analgesic activities.
Curr. Org. Synth., 2019,
16(6), 921-930.
[
http://dx.doi.org/10.2174/1570179416666190703115133] [PMID:
31984913];
h) Abeed, A.A.O.; El-Emary, T.; Alharthi, S. Efficient synthetic access to novel indolo[2,3-b]quinoxaline-based heterocycles.
Curr. Org. Synth., 2022,
19(1), 177-185.
[
http://dx.doi.org/10.2174/1570179418666210809144906] [PMID:
34370643]
[45]
Ilango, K.; Valentina, P. Textbook of Medicinal Chemistry, 1st ed; Keerthi Publishers: India, 2007, pp. 327-333.
[48]
Finney, D.J. Probit analysis, 3rd ed; Cambridge University Press: Cambridge, UK, 1971.