Indian Journal of Chemistry Vol. 56B, February 2017, pp. 192-196
Dependence of biological activities of some chalcone derivatives from the molecular structure I G Mamedov*a, Y V Mamedovaa, V N Khrustalevb, M R Bayramova & A M Maharramova a
b
Baku State University, Chemical Faculty, Z Khalilov 23, Baku, Azerbaijan Peoples Friendship University of Russia, Miklukho-Maklaya, Moscow, Russia E-mail:
[email protected] Received 7 January 2016; accepted (revised) 27 July 2016
The dependence of antibacterial and antifungal activity of five synthesized compounds from the molecular structure are reported. The synthesized compounds at different dynamic conditions have demonstrated poor antifungal, but good antibacterial activities.
Keywords: Antibacterial, antifungal, chalcone, indazole, isoxazole, NMR spectroscopy
The chalcones and their derivatives are important intermediates in organic synthesis. They serve as starting material for the synthesis of a variety of heterocyclic compounds which have physiological significance. Due to their different functionality these compounds confer biological activities, such as antimicrobial, antibacterial, antifungal, anticancer, antitubercular, antiviral, antinflammatory, antihyperglycemic, etc.1-13 Due to the above indicated seriousness problems were investigated biological activities of some chalcone derivatives at different dynamic conditions against S. aureus, E. faecalis, P. aeruginosa, C. albicans and C. bacteria. Staphylococcus aureus and Enterococcus faecalisare gram-positive coccal bacteriums, which can cause a wide spectrum of infections, ranging from simply to potentially fatal diseases. The literature data show that, the incidence of infection due to S. aureus, E. faecalis seems to be the highest in neonates and immunodeficient individuals with a mortality rate is ~50% and indicated infections have high antibiotic resistance threat14-16. Pseudomonas aeruginosa is gram-negative bacterium that can causes disease in humans and animals. The symptoms of such infections are generalized inflammation and sepsis. If such colonizations occur in critical body organs, such as the lungs, the urinary tract, and kidneys, the results can be fatal17. Coliform bacteria- are common bacterial indicators of sanitary quality of food and water. They are defined as rod-shaped gram-negative bacteria.
Candida albicans- is a diploid fungus pathogen and opportunistic human infection, that are transferred through the mouth and genitals. Systemic fungal infections (fungemia) are important causes of morbidity and mortality in immunodeficient patients (such as AIDS, cancer chemotherapy or organ transplant)18. Experimental Section The purity and structure of the synthesized compounds were confirmed by thin layer chromatography (Silufol UV-254, 0.1 mm silica gel plates, iodine vapor as visualizing agent, eluent 5:2 hexane/ethyl acetate), NMR spectroscopy and XRD (for the compound 1) methods. Nuclear magnetic resonance (NMR) spectra were recorded using Bruker AV-300 (300 MHz for 1H NMR, and 75 MHz for 13 C NMR) spectrometer. X-ray structure of single crystal (1) were obtained using BRUKER APEX-II diffractometer.
Synthesis The compound 6-acetyl-5-[2-(allyloxy)-5-bromophenyl] -3-(2-hydroxy-5-methylphenyl)-2-cyclohexen-1-one (1) was obtained by the reaction of 0.01 mol (2E)-3[2-(allyloxy)-5-bromophenyl]-1-(2-hydroxy-5-methylphenyl) -2-propen-1-one (A) with 0.01 mol acetylacetone in 10-15 mL ethanol in the presence of 0.01 mol piperidine at RT and reflux time of 3 h (Scheme I). The reaction mixture was then poured with good stirring into 50 mL ice-cold water and brought to RT until the reaction product separated as a solid. This
MAMEDOV et al.: CHALCONE DERIVATIVES
193 CH3 O + NH2OH . HCl -HCl, H2O
H O
CH3
CH3 O
Br
Br OH
O
O acetylacetone
+
N
-H2O Br
CH3
Br S
OH
OH
O
2
NH
O
1
A
O
O
+ NH2NH-C-NH2
1
- H2O, HO-C-NH2
Br S
OH
OH
CH3
3
O
N O N
O OH
CH3
OH
O
O
OH + NH2OH. . HCl
acetylacetone
-H2O
+ O H
-HCl, H2O
CH3 O 4
CH3
CH3
5
Scheme I — General synthesis reaction scheme of investigated compounds
was filtered off and purified by recrystallization from ethanol (m.p.73-75°C, yield ∼63%). Compound 1: 1H NMR (CCl4, 300 MHz): δ 1.94 (s, CH3), 2.24 (s, CH3), 2.25 (m, CH), 3.05 (m, CH), 3.31 (m, CH2), 4.53 (d, OCH2), 5.4 (d-d, =CH2), 6.43 (s, =CH), 6.69 (m, =CH), 6.76 (CH, arom.), 6.78 (CH, arom.), 6.8 (CH, arom.), 6.86 (CH, arom.), 6.83 (s, OH), 7.21 (s, CH, arom.), 7.25 (CH, arom); 13 C NMR (CCl4, 75 MHz): δ 20.59, 22.77, 31.21, 34.82, 39.82, 68.91, 113.23, 113.50, 116.48, 117.46, 123.43, 126.57, 126.59, 127.48, 128.74, 130.43, 131.08, 133.23, 134.70, 152.20, 153.50, 154.44, 180.4, 191.59. The 2-{4-[2-(allyloxy)-5-bromophenyl]-3-methyl4.5-dihydro-1H-indazol-6-yl}-4-methylphenol (2, m.p. 108-110°C, yield ∼75%), 2-{4-[2-(allyloxy)-5-bromophenyl] -3-methyl-4.5-dihydro-1.2-benzisoxazol-6-yl}-4-methylphenol (3, m.p. 72-74°C, yield ∼75%) and (E)-4-methyl-2-(3methyl-4-styryl-4.5-dihydrobenzoisoxasol-6-yl) phenol (5, m.p. 140°C, yield ∼75%) have been prepared by the known literature methods19. The known compound (2E, 4E)-1(2-hydroxy-5-metilphenyl)-5-phenyl-2,4-pentadien-1on (4) has been prepared by interaction between the 2hydroxy-5-methylacetophenone and cinnamaldehyde in presence of base catalyst (m.p. 56°C, yield 88%, Scheme I). Compound 2: 1H NMR (CDCl3 + CCl4, 300 MHz): δ 2.01 (s, CH3), 2.24 (s, CH3), 2.95 (m, CH2), 4.1 s (NH), 4.1 (s, OH), 4.59 (d, CH2), 4.67 (t, CH), 5.33 (d-d, =CH2), 6.04 (m, =CH), 6.76 (CH, arom.), 6.77 (CH, arom.), 6.80 (CH, arom.), 6.81 (s, =CH), (CH, arom.), 6.95 (CH, arom.), 7.07 (CH, arom.),
7.31 (CH, arom.); 13C NMR (CDCl3 + CCl4, 75 MHz): δ 10.40, 20.61, 30.06, 37.06, 69.06, 112.77, 113.29, 113.59, 115.92, 117.32, 117.99, 118.7, 127.96, 128.78, 128.83, 129.18, 129.91, 131.69, 133.21, 135.68, 137.81, 147.29, 152.14, 154.75. Compound 3: 1H NMR (CDCl3, 300 MHz): δ 2.01 (s, CH3), 2.26 (s, CH3), 3.15 (m, CH2), 4.57 (d, OCH2), 4.65 (t, CH), 5.35 (d-d, CH2), 6.01 (m, =CH), 6.78 (s, =CH), 6.81 s (OH), 6.92 (CH, arom.), 6.98 (CH, arom.), 7.12 (CH, arom.), 7.21 (CH, arom.), 7.31 (CH, arom.), 7.33 (CH, arom.); 13C NMR (CDCl3, 75 MHz): δ 10.03, 20.27, 29.15, 36.90, 69.05, 113.19, 113.65, 113.71, 114.14, 115.90, 117.68, 118.17, 126.80, 128.78, 129.94, 130.75, 130.94, 132.47, 141.04, 147.26, 150.46, 154.43, 157.26, 166.95. Compound 4: 1H NMR (acetone-d6, 300 MHz): δ 2.33 (s, CH3), 6.88 (d, CH), 7.24 (s, CH), 7.25 (m, CH), 7.37 (d, =CH), 7.39 (d, CH), 7.40 (m, CH), 7.43 (m, CH), 7.62 (m, CH), 7.64 (m, CH), 7.87 (m, CH), 12.78 (s, OH); 13 C NMR (acetone-d6, 75 MHz): δ 19.35, 117.9, 119.64, 124.03, 127.07, 127.11, 127.43, 128.90, 129.34, 136.33, 136.37, 137.34, 142.57, 145.32, 161.57, 193.83. Compound 5: 1H NMR (acetone-d6, 300 MHz): δ 2.18 (s, CH3), 2.20 (s, CH3), 3.02 (m, CH), 3.72 (m, CH,), 6.41 (s, =CH), 6.78 (d, =CH), 6.79 (d, arom.), 6.94 (d, =CH), 7.07 (s, arom.), 7.21 (d, arom.), 7.28 (m, arom.), 7.29 (m, arom), 7.37 (d, arom.), 9.68 (s, OH); 13C NMR (acetone-d6, 75 MHz): δ 19.54, 34.09, 35.79, 111.04, 112.86, 113.21, 115.95, 115.96, 126.23, 127.11, 128.48, 128.51, 129.79, 129.81, 130.62, 137.29, 142.67, 152.62, 156.94, 166.36.
INDIAN J. CHEM., SEC B, FEBRUARY 2017
194
method21 has been applied only for compound 1, with P. aeroginosa containing medium prepared from the dressing of surgical patients. In this work differential culture media were used from the company “Liofilchem” (Italy).
Staphylococcus aureus (ATCC 29213), Enterococcus faecium (ATCC 29212) and Candida albicans (ATCC 10231) were obtained from ATCC (Rockville, MD, USA). Coliform bacteria isolates were obtained from water surface reservoirs. Pseudomonas aeroginosa containing medium was prepared from the dressing of surgical patients.
Results and Discussion In the present work antibacterial and antifungal activities of some chalcone derivatives (1-5)22,23 against S. aureus, E. faecalis, P. aeruginosa, C. albicans and C. bacteria have been investigated. The molecular structures of investigated compounds are shown in Scheme II (4 is a known compound in literature). Our DNMR investigations in DMSO-d6, acetone-d6, and CCl4 solutions revealed the possible existence of keto tautomer (a) in CCl4 and keto-enol (a, b) tautomers in DMSO-d6, acetone-d6 solutions for the 6-acetyl-5-[2-(allyloxy)-5-bromophenyl] -3-(2-hydroxy-5-methylphenyl)-2-cyclohexen-1-one (1, Scheme III)22. Single crystal diffraction pattern from the compound 1 is available, and X-ray analysis revealed the existence of only one tautomer (b) in solid (Figure 1).
Antibacterial and antifungal testing Compounds 1-5 were evaluated for their in vitro antibacterial and antifungal activities by agar disc-diffusion method20. Stock solutions of test compounds were diluted in dimethyl sulfoxide (DMSO) to give a final concentration of 30 mg/mL for 1-3, and 1 mg/mL for 4, 5. DMSO alone was used as a control and it was revealed that solvent does not influence to antibacterial-antifungal properties (zone of inhibition was 1-1.5 mm). The plates with bacterial suspensions and disk of investigated compounds were incubated at 37°C for 24 h, for the bacteria and fungi. After incubation, growth was surveyed by measuring the diameter of the growth inhibition zones. The micro-dilution susceptibility CH3
CH3
CH3 O
O
O
Br
Br
Br OH
O
O
OH
OH
1
N
2
NH
N
OH
O
N
3
O
O CH3
OH
4 CH3
5
Scheme II — The molecular structure of investigated componds CH3 O
O
O
Br
Br
Br OH
O
CH3
CH3
O
a)
OH
OH
O
OH
b)
HO
Scheme III — The possibility of tautomeric transitions for the molecule 1 in solutions
O
c)
MAMEDOV et al.: CHALCONE DERIVATIVES
The presence of the keto-enol tautomeric transitions (a, b) in DMSO solutions and (b) in solid state for the molecule 1 were confirmed by the NMR and X-ray investigations22. Taking into account above indicated facts, we carried out testing of antibacterial, antifungal sensitivity of compound 1 in DMSO solution and as powder against S. aureus, P. aeruginosa, C. albicans and C. bacteria. The results showed that compound 1 in DMSO solution (mixture of a, b tautomers) at concentration of 30 mg/mL did not exhibit antifungal properties, whereas they displayed good antibacterial activity against
Figure 1 — X-ray structure of compound 1
195
S. aureus (growth inhibition is 80%), and zone of inhibition against C. bacteria is 21 mm (Table I). The compound 1 as powder (only b tautomer) also did not exhibit antifungal properties and displayed poor antibacterial activity, but displayed good adsorption properties against C. bacteria. As a result of adsorption of bacteria in the medium, the color of compound 1 changed from yellow to red, but the color of medium changed from red to yellow at concentration of 10, 20, 30 mg and zone of inhibition accordingly were 16, 20, 28 mm. Hence, compound 1 as powder (only b tautomer) showed good sorption property against C. bacteria. By micro-dilution susceptibility method antibacterial activity of compound 1 at concentrations of 3.75, 7.5, 15 and 30 mg/mL in DMSO against P. aeroginosa (medium prepared from the dressing of surgical patients) were tested and at 15 mg/mL concentration changing of the color from blue-green to yellow have been observed. Compound 1 showed good antibacterial activity against P. aeroginosa at 15 and 30 mg/mL. The possibility of conformational transitions (a), (b), (c) and (d) for molecule 2-{4-[2-(allyloxy)-5-bromophenyl]3-methyl-4.5-dihydro-1H-indazol-6-yl} -4-methylphenol (2) and 2-{4-[2-(allyloxy)-5-bromophenyl]-3-methyl-4.5dihydro-1.2-benzisoxazol-6-yl} -4-methyl-phenol (3) in DMSO-d6 solutions have been confirmed by DNMR investigations22 (Scheme IV). In compound 2 there are two nitrogen atoms, in comparison to 3 (indazole and oxazole rings accordingly). Taking into account above indicated facts the investigations of antibacterial and antifungal activities of these compounds is of interest.
Table I — Antibacterial and antifungal activity of 1-3 in DMSO solution (30 mg/mL) and 4-5 (1 mg/mL) (disc-diffusion method) Microorganism
Growth inhibition (%) 1 80 − − − −
S. aureus E. faecalis C. bacteria C. albicans DMSO
2 100 − − − −
3 80 − − − −
4 − 70 − − −
Br
CH3
Zone of inhibition (mm) 5 − 80 − − −
1 − − 21 − 1-1.5
2 − − 32 − 1-1.5
CH3
3 − − 27 − 1-1.5
4 28 − − − 1-1.5
OH
O
5 32 − − − 1-1.5
Br
OH
O
O
Br
Br OH
N
X
a)
O
OH
N
X
b)
CH3
N
X
c)
CH3
N
X
d)
X= O, NH
Scheme IV — The possibility of presence of conformational transitions for the molecule 2 and 3 in DMSO-d6 solution
196
INDIAN J. CHEM., SEC B, FEBRUARY 2017
The results showed that compound 2 and 3 in DMSO solution (mixture of a, b, c, d conformers)22 at concentration of 30 mg/mL did not exhibit antifungal properties, whereas they displayed good antibacterial activity against S. aureus (growth inhibitions were 100 and 80% accordingly), and zones of inhibitions against C. bacteria were 32 and 27 mm (Table I). It may be noted that two nitrogen atoms in indazole ring and high molecular mobility have important effects on antibacterial activity of compound 2. For the testing the influence of position of groups on biological activity, known compound 4 and its isoxazole derivative 5 were investigated23. The results showed that compound 4 and 5 in DMSO solution at concentration of 1 mg/mL did not exhibit antifungal properties, whereas they displayed poor antibacterial activity against P. aeroginosa, C. bacteria, but good antibacterial activity against S. aureus (zones of inhibitions were 28 and 32 mm respectively) and E. faecalis (growth inhibitions were 70 and 80% respectively, Table I). The results obtained showed that isoxazole, cyclohexene rings and unsaturated bond imparted high antibacterial activity to molecule 5. To summarize the obtained data, it can be noted that high antibacterial activity of compound 2 against S. aureus, C. bacteria and compound 5 against S. aureus may be connected by presence of indazole ring with the two nitrogen atoms, free phenol hydroxyl group, high molecular mobility in the compound 2 and by presence of conjugated styryl fragment, isoxazole ring and free phenol hydroxyl group in the compound 5. Conclusion The biological activities of some chalcone derivatives have been reported at different dynamic conditions. All the synthesized compounds demonstrated poor antifungal properties, but good antibacterial activity at different dynamic conditions. Structure and dynamics processes in solutions have been confirmed by NMR and by solid state X-ray methods. The compound 1 as powder (in absence of tautomeric transitions) demonstrated good sorption properties against C. bacteria and good antibacterial activity against P. aeroginosa in DMSO solution (in presence of tautomeric mixture). Detailed investigations showed that the best antibacterial activity was demonstrated by compound 2 against S. aureus, C. bacteria in DMSO solutions at concentration of 30 mg/mL (growth inhibitions and zone of inhibition were 100% and 32 mm respectively) and 5 against S. aureus at
concentration 1 mg/mL (zones of inhibition was 32 mm). The obtained results showed that for evaluating the mechanism of processes, NMR as an important tool has theoretical-practical significance in biochemistry, medicine and molecular physics. Supplementary Information Supplementary information is available in the website http://nopr.niscair.res.in/handle/123456789/60. References 1 Nowakowska Z, Kedzia B & Schroeder G, Eur J Med Chem, 43, (2008), 707. 2 Mishra N, Arora P, Kumar B, Mishra L C, Bhattacharya A, Awasthi S K & Bhasin V K, Eur J Med Chem, 43, (2008), 1530. 3 Yar M S, Siddiqui A A & Ali M A, J Serb Chem Soc, 7, (2007), 25. 4 Doan T N & Tran D H, J Pharm Pharmacol, 2, (2011), 282. 5 Patil S G, Utale P S, Gholse S B, Thakur S D & Pande S V, Chem Pharm Res, 4, (2012), 501. 6 Dong X, Liu T, Yan J, Wu P, Chen J & Hu Y, Bioorg Med Chem, 17 (2009) 716. 7 Katade S, Phalgune U, Biswas S, Wakhardar R & Deshpandey N, Indian J Chem, 47B, (2008), 927. 8 Khatib S, Nerya O, Musa R, Shmuel M, Tamir S & Vaya J, Bioorg Med Chem, 13, (2005), 433. 9 Sharma V & Sharma K V, Elec J Chem, 7, (2010), 203. 10 Hsieh H K, Tsao L T, Wang J P & Lin C N, J Pharm Pharmacol, 52, (2000), 163. 11 Ram V J, Saxena A S, Srivastava S & Chandra S, Bioorg Med Chem Lett, 10, (2000), 2159. 12 Zhai L, Chen M, Blom J, Theander T G, Chiristensen S B & Kharazmi A, J Antimicrob Chemother, 43, (1999), 793. 13 Dhar D N, The chemistry of chalcones and related compounds, (Wiley, New York), p.285 (1981). 14 Koneni V S, Rao K B, Kushwaha P, Modukuri R K, Singh P, Soni I, Shukla P K, Chopra S & Pasupuleti M, Med Chem Lett, 7, (2015), 809. 15 Maria de Fátima S L, Tânia R, Abrantes M, José J F M, Tenreiro R, Teresa M & Crespo B, Int J Food Microbiol, 103, (2005), 191. 16 Giraffa G, FEMS Microbiol Rev, 26, (2002), 163. 17 Balcht A & Smith R, Pseudomonas aeruginosa: Infections and Treatment (Informa Health Care) p.83-84 (1994). 18 Ryan K J & Ray C G, Sherris Medical Microbiology (McGraw Hill, USA), p.937 (2004). 19 L F Tietze & Th Eicher, Reaktionen und Synthesen im Organisch-Chemischen Praktikum und Forschungslaboratorium (Georg Thieme Verlag, Stuttgart, New York) (1991). 20 Approved Standard Document M-7A. NCCLS; Villanova, PA. National Committee for Clinical Laboratory Standards. USA (1985). 21 Murray P R, Baron E, Jorgensen J, Landry M & Pfaller M, Manual of Clinical Microbiology (ASM Press, Washington DC), p.2488 (2007). 22 Mamedov I G, Bayramov M R, Mamedova Y V & Maharramov A M, Magn Reson Chem, 53, (2015), 147. 23 Mamedov I G, Bayramov M R, Mamedova Y V & Maharramov A M, Magn Reson Chem, 51, (2013), 600.
