Synthesis of glycerol-derived 4-alkyl-substituted 1,2,3-triazoles and evaluation of their fungicidal, phytotoxic, and antiproliferative activities

Article abstract of DOI:10.21577/0103-5053.20190246

Herein, the synthesis of nine novel glycerol-derived 4-alkyl-substituted 1,2,3-triazoles, using the Cu^I-catalyzed alkyne-azide cycloaddition reaction as the key step, is reported. The triazoles were characterized by infrared and nuclear magnetic resonance (NMR ¹H and ¹³C) spectroscopy and mass spectrometry. The nine prepared compounds were evaluated with regard to their phytotoxic, antiproliferative, and fungicidal activities. The fungicidal activity was assessed on Colletotrichum gloeosporioides, the causative agent of papaya anthracnose. All compounds presented high efficiency (comparable to the commercial fungicide tebuconazole) in inhibiting C. gloeosporioides sporulation. The phytotoxicity of the triazoles was assessed against Lactuca sativa. Germination was the less-affected parameter, whereas the most pronounced effects of the triazoles were on the germination speed index and root growth of the L. sativa seedlings. As indicators of antiproliferative activity, the mitotic index was evaluated along with chromosomal and nuclear alterations, all of which were influenced to different degrees by the triazoles. In addition, all derivatives demonstrated aneugenic and clastogenic actions in meristematic cells of L. sativa roots. Therefore, these 4-alkyl-substituted triazoles may represent a scaffold to be explored for the development of new fungicidal agents.

Full text of DOI:10.21577/0103-5053.20190246

http://dx.doi.org/10.21577/0103-5053.20190246
J. Braz. Chem. Soc., Vol. 00, No. 00, 1-12, 2019
Printed in Brazil - ©2019 Sociedade Brasileira de Química
Article
Synthesis of Glycerol-Derived 4-Alkyl-Substituted 1,2,3-Triazoles and Evaluation of
Their Fungicidal, Phytotoxic, and Antiproliferative Activities
Adilson V. Costa, a Luiza C. Moreira,a Roberta T. Pinto,a Thammyres A. Alves,b
b
Vitor V. Schwan,b Vagner T. de Queiroz,a Milene M. Praça-Fontes,
Róbson Ricardo Teixeira, *,c Pedro A. B. Moraisa and Waldir C. de Jesus Júniord
aDepartamento de Química e Física, Universidade Federal do Espírito Santo,
Alto Universitário, s/n, Guararema, 29500-000 Alegre-ES, Brazil
bDepartamento de Biologia, Universidade Federal do Espírito Santo,
Alto Universitário, s/n, Guararema, 29500-000 Alegre-ES, Brazil
cDepartamento de Química, Universidade Federal de Viçosa,
Av. P.H. Rolfs, s/n, 36570-900 Viçosa-MG, Brazil
dUniversidade Federal de São Carlos, Campus Lagoa do Sino, 18290-000 Buri-SP, Brazil
Herein, the synthesis of nine novel glycerol-derived 4-alkyl-substituted 1,2,3-triazoles,
using the CuI-catalyzed alkyne-azide cycloaddition reaction as the key step, is reported. The
1
triazoles were characterized by infrared and nuclear magnetic resonance (NMR H and 13C)
spectroscopy and mass spectrometry. The nine prepared compounds were evaluated with regard
to their phytotoxic, antiproliferative, and fungicidal activities. The fungicidal activity was
assessed on Colletotrichum gloeosporioides, the causative agent of papaya anthracnose. All
compounds presented high efficiency (comparable to the commercial fungicide tebuconazole) in
inhibiting C. gloeosporioides sporulation. The phytotoxicity of the triazoles was assessed against
Lactuca sativa. Germination was the less-affected parameter, whereas the most pronounced effects
of the triazoles were on the germination speed index and root growth of the L. sativa seedlings. As
indicators of antiproliferative activity, the mitotic index was evaluated along with chromosomal and
nuclear alterations, all of which were influenced to different degrees by the triazoles. In addition,
all derivatives demonstrated aneugenic and clastogenic actions in meristematic cells of L. sativa
roots. Therefore, these 4-alkyl-substituted triazoles may represent a scaffold to be explored for
the development of new fungicidal agents.
Keywords: 1,3-dipolar cycloaddition, 1,4-disubstituted 1,2,3-triazoles, click chemistry,
antiproliferative activity, phytotoxicity, glycerol
Introduction
cytotoxic,9,10 antiviral,11,12 antimalaric,13,14 leishmanicidal,15
anticancerous,16,17 phytotoxic effects,18 among others.19,20 In
addition, the monocyclic 1,2,3-triazoles and benzotriazoles
present stability towards hydrolysis, oxidative/reductive
conditions, and enzymatic degradation.21 Some unique
features of the triazole compounds, such as their capabilities
of hydrogen-bond formation and dipole-dipole and pi-
stacking interactions, have increased their importance in
the field of medicinal chemistry, as they bind to biological
targets with high affinity owing to their improved
solubility.20
Heterocyclics are a group of structurally diverse
compounds that play important roles in the pharmaceutical
and agrochemical fields.1-3 The major classes of
heterocyclic contain oxygen, sulfur, and nitrogen in their
composition.
Among the several classes of heterocyclic, the
1,2,3-triazoles have received considerable attention from
research groups. These five-membered scaffolds are
exclusively synthetic in nature, and present a vast array of
biological activities, including antibacterial,4-7 antifungal,8
Glycerol is a byproduct generated during the
transesterification of vegetable oils and fats. It is an
abundant natural polyol that exists in nature in the form
*e-mail: robsonr.teixeira@ufv.br

2
Synthesis of Glycerol-Derived 4-Alkyl-Substituted 1,2,3-Triazoles
J. Braz. Chem. Soc.
of triacylglycerides. Since its discovery in 1779, chemists
have been finding applications for glycerol, which is used
widely in the pharmaceutical and cosmetic industries.22,23
Other applications include its uses as a plasticizer in the
polymer industry and as a moistening agent or solvent in
the food industry.24 This compound has also found several
applications as a building block for the construction
of useful chemicals25-28 and as a medium for chemical
reactions.29,30 Moreover, glycerol has been used for the
preparation of bioactive compounds.31
In a previous investigation,32 we used glycerol as the
starting material for the synthesis of triazolic derivatives
presenting the general structure I (Figure 1), and assessed
their fungicidal, phytotoxic, and cytotoxic activities. It was
noticed that the biological activities of the derivatives I
were significantly influenced by the nature of the X group
attached to the triazole ring.
Experimental
Generalities
Terminal alkynes were purchased from Sigma-Aldrich
(St. Louis, MO, USA) and used without further purification.
The solvents and other reagents were procured from Vetec
(Rio de Janeiro, Brazil) and used without further purification.
The 1H and 13C nuclear magnetic resonance (NMR) spectra
were recorded on aVarian Mercury 300 instrument (Varian,
Palo Alto, CA, USA), at 300 MHz for 1H and 75 MHz for
13C, using CDCl3 as the solvent and tetramethylsilane as
1
the internal standard. The H NMR data are presented as
follows: chemical shift (d) in ppm, multiplicity, the number
of protons, and J values in Hertz (Hz). Multiplicities
are indicated by the following abbreviations: s (singlet),
d (doublet), dd (double of doublets), t (triplet), q (quartet),
quint (quintet), sept (septet), and m (multiplet). The infrared
(IR) spectra were acquired using a Tensor 27 device and the
attenuated total reflection technique (ATR, Bruker, Karlsruhe,
Germany), with scanning from 500 to 4000 cm−1. Melting
points were determined using a MA 381 melting point
apparatus (Marconi, São Paulo, Brazil), and are uncorrected.
The progress of the reactions was monitored by thin-layer
chromatography (TLC). Flash column chromatography was
performed using a silica gel (70-230 mesh).
Figure 1. General structure of glycerol triazolic derivatives I.
Previous reports in the literature have demonstrated
the influence of alkyl groups in the biological response of
bioactive substances. For example, 2,5-bis(alkylamino)-
1,4-benzoquinones present phytotoxic and cytotoxic
effects that vary significantly with the size of the alkyl
group.33,34 More recently, eugenol derivatives, containing
different aliphatic chains with the parent molecule via
an ether or ester linkage, were prepared and had their
leishmanicide activity evaluated. From this investigation,
a potent compound against visceral leihsmaniasis was
found.35 It is important to mention that the variation of the
length of alkyl group impact on solubility, increasing or
decreasing partial atomic charge of pharmacophore site,
and the total volume of resulting molecule. These, in turn,
have a direct impact on bioactivity. The aforementioned
precedents illustrate that variations of alkyl groups in a
scaffold can result in the discovery of new compounds
with significant bioactivities. Considering these facts
and with the aim of obtaining compounds with improved
biological activity based on scaffold I, we have prepared
novel glycerol derivatives bearing different alkyl
substituents attached to the triazole functional group.
The compounds were evaluated for their phytotoxic,
antiproliferative, and fungicidal activities.
Synthesis
The compounds (2,2-dimethyl-1,3-dioxolan-4-yl)
methanol (1), (2,2-dimethyl-1,3-dioxolan-4-yl)methyl-
4-methylbenzenesulfonate (2) and 4-(azidomethyl)-
2,2-dimethyl-1,3-dioxolane (3) were synthesized as
previously described in the literature.32
General procedure for the synthesis of triazoles 4a-4i
The azide 3 (1.00 g, 6.40 mmol), terminal alkyne
(9.60 mmol), aqueous solution of tert-butyl alcohol (6 mL
of water and 6 mL of tert-butyl alcohol), CuSO4∙5H2O
aqueous solution (0.100 mol L–1, 1.00 mL, 0.0960 mmol),
and sodium ascorbate (0.0600 g, 0.288 mmol) were added
to a round-bottomed flask and the reaction mixture was
stirred at 50 °C for 8 h.After the end of the reaction (verified
by TLC analysis), distilled water (10.0 mL) was added and
the aqueous layer was extracted with dichloromethane
(3 × 20 mL). The organic extracts were combined and
the resulting organic phase was dried over anhydrous
sodium sulfate, filtered, and concentrated under reduced
pressure. The residue was purified by silica gel column
chromatography, eluted with ethyl acetate-methanol

Vol. 00, No. 00, 2019
Costa et al.
3
(9:1 v/v). The described procedure afforded triazoles 4a-4i
in 65-84% yields. The structures of compounds 4a-4i were
supported by the following data.
(75 MHz, CDCl3) d 14.2, 22.6, 25.5, 25.8, 26.9, 29.3, 31.6,
52.1, 66.6, 74.3, 110.3, 122.1, 148.7; MS (m/z, %) 253 ([M+],
12), 238 ([M − 15]+, 50), 195 (47), 178 (11), 138 (27), 124
(69), 110 (36), 101 (49), 73 (30), 57 (73), 43 (100), 30 (10).
Synthesis of 1-((2,2-dimethyl-1,3-dioxolan-4-yl)methyl)-
4-propyl-1H-1,2,3-triazole (4a)
Synthesis of 1-((2,2-dimethyl-1,3-dioxolan-4-yl)methyl)-
4-hexyl-1H-1,2,3-triazole (4d)
Yellow liquid, prepared in 85% yield from the reaction
between pent-1-yne (1.30 g, 19.2 mmmol) and azide 3
(2.00 g, 12.8 mmol); TLC (ether-dicloromethane 10:1 v/v)
White solid, prepared in 75% yield from the reaction
between oct-1-yne (2.11 g, 19.2 mmmol) and azide 3
(2.00 g, 12.8 mmol); TLC (ether-dichloromethane 10:1 v/v)
–
Rf = 0.61; IR (ATR) vmax / cm−1 2984, 1372, 1216, 1064,
–
1
832, 798; H NMR (300 MHz, CDCl3) d 0.93 (t, 3H,
Rf = 0.68; mp 58-60 ºC; IR (ATR) vmax / cm−1 2871, 1372,
1
J 9.0 Hz), 1.31 (s, 3H), 1.34 (s, 3H), 1.67 (sept, 2H,
J 9.0 Hz), 2.66 (t, 2H, J 9.0 Hz), 3.70 (dd, 1H, J 9.0, 6.0 Hz),
4.07 (dd, 1H, J 9.0, 6.0 Hz), 4.37 (dd, 1H, J 12.0, 6.0 Hz),
4.40-4.45 (m, 1H), 4.48 (dd, 1H, J 12.0, 3.0 Hz), 7.38 (s,
1H); 13C NMR (75 MHz, CDCl3) d 14.0, 22.9, 25.4, 26.8,
27.8, 52.1, 66.6, 74.3, 110.2, 122.2, 148.3; MS (m/z, %)
225 ([M+], 4), 210 ([M − 15]+, 3), 168 (11), 167 (46), 150
(13), 125 (13), 110 (50), 101 (30), 82 (1), 73 (27), 68 (35),
57 (57), 43 (100), 32 (17).
1216, 1147, 1076, 1014, 844, 798; H NMR (300 MHz,
CDCl3) d 0.86 (t, 3H, J 9.0 Hz), 1.30 (sept, 6H, J 9.0 Hz),
1.33 (s, 3H), 1.35 (s, 3H), 1.64 (quint, 2H, J 9.0 Hz), 2.69
(t, 2H, J 9.0 Hz), 3.70 (dd, 1H, J 9.0, 6.0 Hz), 4.07 (dd, 1H,
J 9.0, 6.0 Hz), 4.37 (dd, 1H, J 12.0, 6.0 Hz), 4.40-4.46 (m,
1H), 4.49 (dd, 1H, J 12.0, 6.0 Hz), 7.39 (s, 1H); 13C NMR
(75 MHz, CDCl3) d 14.2, 22.7, 25.4, 25.8, 26.8, 29.1, 29.6,
31.7, 52.1, 66.6, 74.3, 110.3, 122.1, 148.6; MS (m/z, %)
267 ([M+], 15), 252 ([M − 15]+, 52), 209 (40), 192 (10),
168 (9), 152 (20), 138 (67), 124 (22), 101 (52), 96 (36), 68
(39), 57 (71), 43 (100), 30 (10).
Synthesis of 1-((2,2-dimethyl-1,3-dioxolan-4-yl)methyl)-
4-butyl-1H-1,2,3-triazole (4b)
White solid, prepared in 93% yield from the reaction
between hex-1-yne (1.60 g, 19.2 mmmol) and azide 3
(2.00 g, 12.8 mmol); TLC (ether-dichloromethane 10:1 v/v)
Synthesis of 4-(1-((2,2-dimethyl-1,3-dioxolan-4-yl)methyl)-
4-(4-hydroxybutyl)-1H-1,2,3-triazole (4e)
Yellow solid, prepared in 81% yield from the reaction
between hex-5-yn-1-ol (1.40 g, 14.4 mmmol) and azide 3
(1.50 g, 9.60 mmol); TLC (ether-dichloromethane 10:1 v/v)
–
Rf = 0.60; mp 52-53 ºC; IR (ATR) vmax / cm−1 3067, 2927,
1312, 1236, 1183, 1014, 844, 798, 648; 1H NMR (300 MHz,
CDCl3) d 0.93 (t, 3H, J 9.0 Hz), 1.34 (s, 3H), 1.37 (s, 3H),
1.38 (sept, 2H, J 9.0 Hz), 1.68 (quint, 2H, J 9.0 Hz), 2.71
(t, 2H, J 9.0 Hz), 3.77 (dd, 1H, J 9.0, 6.0 Hz), 4.10 (dd,
1H, J 9.0, 6.0 Hz), 4.40 (dd, 1H, J 12.0, 6.0 Hz), 4.40-
4.45 (m, 1H), 4.51 (dd, 1H, J 12.0, 6.0 Hz), 7.40 (s, 1H);
13C NMR (75 MHz, CDCl3) d 14.0, 22.5, 25.5, 25.5, 26.8,
31.7, 52.2, 66.6, 74.4, 110.3, 122.1, 148.7; MS (m/z, %)
239 ([M+], 6), 124 ([M − 15]+, 25), 224 (40), 181 (48), 164
(11), 139 (16), 110 (66), 101 (38), 82 (27), 68 (41), 57 (74),
43 (100), 31 (10).
–
Rf = 0.15; mp 57-58 ºC; IR (ATR) vmax / cm−1 3450, 3059,
2933, 1269, 1203, 1051, 883, 837, 791; 1H NMR (300 MHz,
CDCl3) d 1.32 (s, 3H), 1.35 (s, 3H), 1.61 (quint, 2H,
J 12.0 Hz) 1.74 (quint, 2H, J 9.0 Hz), 2.41 (s, 1H, OH), 2.72
(t, 2H, J 9.0 Hz), 3.66 (dd, 1H, J 9.0, 6.0 Hz), 4.08 (dd, 1H,
J 9.0, 6.0 Hz), 4.34 (dd, 1H, J 12.0, 6.0 Hz), 4.35-4.45 (m,
1H), 4.48 (dd, 1H, J 12.0, 6.0 Hz), 7.42 (s, 1H); 13C NMR
(75 MHz, CDCl3) d 25.2, 25.5, 26.6, 32.1, 52.0, 62.1, 66.4,
74.1, 110.1, 122.1, 148.0; MS (m/z, %) 255 ([M+], 3), 240
([M − 15]+, 8), 210 (13), 197 (10), 126 (7), 101 (13), 69
(13), 57 (21), 43 (53), 32 (100).
Synthesis of 1-((2,2-dimethyl-1,3-dioxolan-4-yl)methyl)-
4-pentyl-1H-1,2,3-triazole (4c)
Synthesis of 1-((2,2-dimethyl)1,3-dioxolan-4-yl)-4-heptyl-
1H-1,2,3-triazole (4f)
White solid, prepared in 87% yield from the reaction
between hep-1-yne (1.80 g, 19.2 mmmol) and azide 3
(2.00 g, 12.8 mmol); TLC (ether-dichloromethane 10:1 v/v)
White solid, prepared in 85% yield from the reaction
between non-1-yne (1.78 g, 14.4 mmmol) and azide 3
(1.50 g, 9.60 mmol); TLC (ether-dichloromethane 10:1 v/v)
–
Rf = 0.60; mp 32-33 ºC; IR (ATR) vmax / cm−1 2968, 2926,
–
1380, 1269, 1204, 1062, 1032, 884, 836;1H NMR (300 MHz,
CDCl3) d 0.88 (t, 3H, J 9.0 Hz), 1.33 (s, 3H), 1.36 (s, 3H),
1.37 (sept, 4H, J 9.0 Hz), 1.65 (quint, 2H, J 9.0 Hz), 2.70
(t, 2H, J 9.0 Hz), 3.71 (dd, 1H, J 9.0, 6.0 Hz), 4.09 (dd, 1H,
J 9.0, 6.0 Hz), 4.39 (dd, 1H, J 12.0, 9.0 Hz), 4.38-4.46 (m,
1H), 4.50 (dd, 1H, J 12.0, 9.0 Hz), 7.39 (s, 1H); 13C NMR
Rf = 0.68; mp 45-47 ºC; IR (ATR) vmax / cm−1 2954, 2919,
1
2851, 2360, 1380, 1320, 1150, 1030, 924; H NMR
(300 MHz, CDCl3) d 0.85 (t, 3H, J 9.0 Hz), 1.29 (sept,
8H, J 9.0 Hz), 1.33 (s, 3H), 1.35 (s, 3H), 1.64 (quint, 2H,
J 9.0 Hz), 2.69 (t, 2H, J 9.0 Hz), 3.69 (dd, 1H, J 9.0, 6.0 Hz),
4.09 (dd, 1H, J 9.0, 6.0 Hz), 4.32 (dd, 1H, J 12.0, 6.0 Hz),

4
Synthesis of Glycerol-Derived 4-Alkyl-Substituted 1,2,3-Triazoles
J. Braz. Chem. Soc.
4.39-4.43 (m, 1H), 4.43 (dd, 1H, J 12.0, 6.0 Hz), 7.39 (s, 1H);
13C NMR (75 MHz, CDCl3) d 14.0, 22.6, 22.2, 25.6, 26.6,
29.0, 29.1, 29.4, 31.7, 51.9, 66.4, 74.1, 110.0, 122.0, 148.5;
MS (m/z, %) 281 ([M+], 13), 266 ([M − 15]+, 44), 223 (25),
210 (10), 197 (21), 166 (16), 152 (41), 138 (19), 124 (21),
110 (60), 101 (46), 82 (27), 68 (39), 57 (64), 43 (100), 30 (8).
2916, 2848, 2360, 1682, 1558, 1540, 1269, 1063, 837;
1H NMR (300 MHz, CDCl3) d 0.85 (t, 3H, J 9.0 Hz), 1.30
(sext, 14H, J 9.0 Hz), 1.32 (s, 3H), 1.35 (s, 3H), 1.64 (quint,
2H, J 9.0 Hz), 2.68 (t, 2H, J 9.0 Hz), 3.70 (dd, 1H, J 12.0,
6.0 Hz), 4.07 (dd, 1H, J 12.0, 6.0 Hz), 4.35 (dd, 1H, J 9.0,
6.0 Hz), 4.39-4.44 (m, 1H), 4.45 (dd, 1H, J 9.0, 6.0 Hz),
7.39 (s, 1H); 13C NMR (75 MHz, CDCl3) d 14.0, 22.6, 25.2,
25.6, 26.6, 29.1, 29.2, 29.3, 29.4, 29.5, 29.5, 31.8, 51.9, 66.4,
74.1, 110.0, 121.9, 148.4; MS (m/z, %) 323 ([M+], 3), 308
([M − 15]+, 9), 210 (2), 194 (7), 168 (2), 152 (3), 138 (5),
124 (6), 110 (19), 96 (11), 69 (18), 57 (17), 44 (34), 32 (100).
Synthesis of 1-((2,2-dimethyl-1,3-dioxolan-4-yl)methyl)-
4-octyl-1H-1,2,3-triazole (4g)
White solid, prepared in 92% yield from the reaction
between dec-1-yne (1.98 g, 14.4 mmmol) and azide 3
(1.50 g, 9.60 mmol); TLC (ether-dichloromethane 10:1 v/v)
–
Rf = 0.69; mp 64-65 ºC; IR (ATR) vmax / cm−1 2991, 2949,
Evaluation of phytotoxic and antiproliferative activities
1
2922, 2872, 2360, 1458, 1372, 1101, 844; H NMR
(300 MHz, CDCl3) d 0.85 (t, 3H, J 9.0 Hz), 1.25 (sept,
10H, J 9.0 Hz), 1.31 (s, 3H), 1.34 (s, 3H), 1.63 (quint, 2H,
J 9.0 Hz), 2.68 (t, 2H, J 9.0 Hz), 3.70 (dd, 1H, J 9.0, 6.0 Hz),
4.08 (dd, 1H, J 9.0, 6.0 Hz), 4.36 (dd, 1H, J 12.0, 6.0 Hz),
4.35-4.45 (m, 1H), 4.49 (dd, 1H, J 12.0, 6.0 Hz), 7.47 (s,
1H); 13C NMR (75 MHz, CDCl3) d 14.0, 22.6, 25.2, 25.6,
26.6, 29.1, 29.2, 29.3, 29.4, 31.8, 51.9, 66.4, 74.1, 110.0,
121.9, 148.4; MS (m/z, %) 295 ([M+], 15), 280 ([M − 15]+,
48), 237 (19), 210 (9), 197 (27), 180 (14), 166 (40), 138
(21), 124 (25), 110 (68), 101 (50), 82 (29), 68 (40), 57 (67),
43 (100), 32 (93).
Analyses of the compounds phytotoxic and
antiproliferative activities were carried out on seeds of
the L. sativa plant.32,36 The experiment was conducted in
a completely randomized design, with nine treatments
(4a-4i compounds), five concentrations (1, 10, 100, 500,
and 1000 μg mL–1), and four replicates each. The negative
controls were distilled water and dichloromethane (DCM),
and the positive control was the commercial herbicide
picloram (1000 ppm).
Twenty-five lettuce seeds were placed in 9-cm-diameter
Petri dishes containing a filter paper, and 2.5 mL of the
test substances dissolved in DCM were subsequently
added to the appropriately marked dishes. After sealing
with film paper, the dishes were placed in a biochemical
oxygen demand (BOD)-type germination chamber at room
temperature (24 2 °C). The percentage of germination
(G%) and germination speed index (GSI) were evaluated
every 8 h for 48 h.After 48 h, the root length was measured
for the indication of root growth (RG), as described by
Pinheiro et al.37
To perform the microscopic analysis, ten roots from
each Petri dish were collected after 48 h of treatment
exposure, fixed in an ethanol-acetic solution (3:1 v/v), and
stored at −4 °C. The slides were prepared according to the
squash technique and stained with 2% (v/v) acetic orcein.
After evaluation of the slides, the mitotic index (MI) and
chromosomal alterations (CA%) and nuclear alterations
(NA%) were determined.
The obtained data were submitted to analysis of
variance and the means were analyzed using Dunnett’s test
(p < 0.05) to compare the treatments with the controls.38
All analyses were performed using the statistical analysis
program GENES VS 2015.5.0.39
Synthesis of 1-((2,2-dimethyl-1,3-dioxolan-4-yl)methyl)-
4-nonyl-1H-1,2,3-triazole (4h)
White solid, prepared in 88% yield from the reaction
between undec-1-yne (0.500 g, 3.28 mmmol) and azide 3
(0.562 g, 3.62 mmol); TLC (ether-dichloromethane
–
10:1 v/v) Rf = 0.69; mp 55-57 ºC; IR (ATR) vmax / cm−1
2922, 2852, 2360, 1507, 1307, 1258, 1184, 1076, 845;
1H NMR (300 MHz, CDCl3) d 0.85 (t, 3H, J 9.0 Hz),
1.25 (sext, 6H, J 9.0 Hz), 1.33 (s, 3H), 1.36 (s, 3H), 1.65
(quint, 2H, J 9.0 Hz), 2.69 (t, 2H, J 9.0 Hz), 3.71 (dd, 1H,
J 9.0, 6.0 Hz), 4.09 (dd, 1H, J 9.0, 6.0 Hz), 4.36 (dd, 1H,
J 12.0, 6.0 Hz), 4.42-4.45 (m, 1H), 4.46 (dd, 1H, J 12.0,
6.0 Hz), 7.48 (s, 1H); 13C NMR (75 MHz, CDCl3) d 14.0,
22.6, 25.2, 25.6, 26.6, 29.1, 29.2, 29.3, 29.4, 31.8, 51.9,
66.4, 74.1, 110.0, 121.9, 148.4; MS (m/z, %) 309 ([M+],
16), 294 ([M − 15]+, 47), 251 (14), 210 (11), 197 (32), 180
(37), 166 (15), 152 (16), 138 (23), 124 (27), 110 (75), 96
(43), 68 (41), 57 (68), 43 (100), 32 (29).
Synthesis of 1-((2,2-dimethyl-1,3-dioxolan-4-yl)methyl)-
4-decyl-1H-1,2,3-triazole (4i)
White solid, prepared in 94% yield from the reaction
between dodec-1-yne (2.39 g, 14.4 mmmol) and azide 3
(1.50 g, 9.60 mmol); TLC (ether-dichloromethane 10:1 v/v)
Evaluation of fungicidal activity
–
Rf = 0.53; mp 54-56 ºC; IR (ATR) vmax / cm−1 3063, 2954,
To evaluate the fungicidal effects of the triazoles 4a-4i

Vol. 00, No. 00, 2019
Costa et al.
5
on C. gloeosporioides, the experiment was conducted
in a completely randomized design, with five replicates
per treatment, consisting of each compound at the
concentrations of 1, 10, 100, 500, and 1000 μg mL–1. The
fungicide tebuconazole was used as a positive control
and a solution of 3.5% (v/v) dimethylsulfoxide (DMSO)
as a negative control. The fungicides were incorporated
into a potato-dextrose-agar (PDA) medium from aqueous
solutions containing 3.5% (v/v) DMSO and distributed in
Petri dishes. The C. gloeosporioides isolate was obtained
from tissues of damaged papaya fruits. Pure cultures were
incubated in a PDA medium at 25 °C for 10 days.
The fungicidal activity was determined according to
the sensitivity of the C. gloeosporioides mycelial growth
and sporulation to the treatments applied, according to
the methodology described by Edgington et al.40 and
Rampersad and Teelucksingh,41 with modifications. Discs
with mycelia were placed in the center of the Petri dishes
containing the different treatments. The plates were
maintained at 25 1 °C, with a photoperiod of 12 h, and
mycelial growth was estimated daily.
After the mycelial growth evaluation, a spore
suspension was prepared for each treatment by adding
distilled water (10 mL) to the Petri dishes. With the help
of a Drigalski spatula, slight friction was applied to the
fungal colonies to release the reproductive structures of
the fungus into the culture medium. The obtained mixture
was filtered through a gauze layer in a glass funnel. The
suspension obtained was homogenized and the number
of conidia in a Neubauer chamber was determined. The
response variables were the percentage of inhibition of
mycelial growth (PIMG) and percentage of inhibition of
sporulation (PIS).
low efficiency (LE) or low sensitivity (LS); and
(iv) ED50 > 50 ppm: not efficient (NE) or not sensitive (NS).
Results and Discussion
Synthesis of glycerol derivatives
The reactions used for the preparation of triazoles 4a-
4i are outlined in Scheme 1. As indicated in Scheme 1,
glycerol was converted to acetonide (1) using standard
methodology. Then, treatment of compound 1 with tosyl
chloride produced the sulfonate ester (2) in 75% yield. The
SN2 reaction between 2 and sodium azide afforded 3 in 93%
yield. Finally, the CuI-catalyzed alkyne-azide cycloaddition
reaction (CuAAC reaction, also known as the click reaction)
between azide (3) and different aliphatic terminal alkynes
resulted in the formation of triazoles 4a-4i in 75-93%
yields (Scheme 1).
The structures of the triazolic derivatives 4a-4i were
confirmed upon IR and 1H and 13C NMR spectroscopy as
well as mass spectrometry analyses. In the IR spectra, the
band corresponding to the =C–H stretching was observed
within the 3063-3083 cm–1 range. In the 1H NMR spectra,
signals corresponding to the hydrogens of the triazole rings
and acetonide methyl groups were observed within the
7.38-7.48 and 1.31-1.37 ppm ranges, respectively. In the
13C NMR spectra, signals for the acetonide methyl groups
were observed within 25.2-26.8 ppm, whereas the carbons
of the triazolic moiety appeared at 121.9-148.7 ppm. The
molecular formulas for the triazolic derivatives were
confirmed on the basis of the mass spectrometry results.
Biological evaluation
Data analysis
With compounds 4a-4i in hand, we turned our attention
to the evaluation of their phytotoxic, antiproliferative, and
fungicidal activities. In the phytotoxic evaluation (Table 1),
the parameter least affected by the nine triazolic derivatives
was the germination of Lactuca sativa. The treatment
effects were statistically similar to those of the negative
controls (water and DCM), except for the 1000 μg mL–1 4c
treatment, which caused a 35% reduction in germination.
This parameter seems to be the least sensitive of the
variables evaluated in macroscopic tests.43
The data obtained for the PIMG and PIS variables were
submitted to regression analysis and, through adjustments
of the inhibition curves, the ED50 and ED100 values
(concentration of the active ingredient of the fungicide
necessary to inhibit 50 and 100% of the mycelial growth
and sporulation of the pathogen) were obtained. The
analyses were made with the software R (R Core Team
2013) and Polo-PC.42
After the ED50 calculation, the fungicides were grouped
according to their efficiency, and the C. gloeosporioides
isolate was rated for its sensitivity toward the fungicides
according to the scale of Edgington et al.40 as follows:
(i) ED50 < 1 ppm: high efficiency (HE) or high sensitivity
(HS); (ii) ED50 1-10 ppm: moderate efficiency (ME)
or moderate sensitivity (MS); (iii) ED50 10-50 ppm:
The most pronounced effects of the triazolic derivatives
were observed on the GSI and RG of L. sativa seedlings.
The derivatives 4a, 4b, 4c, 4d, 4f, and 4h influenced the
reduction of the presented GSI and RG means, especially
at the higher concentrations (500 and 1000 μg mL–1).
In addition, for derivative 4c at the concentration of
1000 μg mL–1, the 68.53 and 85.78% reduction in GSI and

6
Synthesis of Glycerol-Derived 4-Alkyl-Substituted 1,2,3-Triazoles
J. Braz. Chem. Soc.
Scheme 1. Synthesis of 1,2,3-triazoles 4a-4i. Glycerol was used as the starting material for preparation of the new triazolic derivatives. Intermediates 1,
2 and 3 were obtained in 63, 75 and 93% yields, respectively. Compounds 4a-4i were obtained in 75-94% yields.
RG values, respectively, were statistically similar to those
of the positive control.
derivatives containing halogenated benzyl groups and
compared their reduction of RG in onion (Allium cepa,
another widely used species in phytotoxic bioassays) with
that by 2,4-dichlorophenoxyacetic acid (a commercial
herbicide popularly known as 2,4-D).
Derivative 4e at the concentrations of 500 and
1000 μg mL–1 increased the RG means of the L. sativa seeds,
showing statistically significant differences compared
with the positive and negative controls. This increase may
have been due to the cellular elongation that occurs in the
processes of growth and differentiation.44 Among several
other processes, cellular differentiation is dependent on
the activity of enzymes acting on cell expansion, cell wall
remodeling, and cellulose deposition, linked to turgescence,
via water absorption.45 It is possible that some of these
factors were influenced by the action of 4e.
Costa et al.32 evaluated the effects of other glycerol-
derived triazoles on L. sativa. However, the authors did not
observe any influence of the derivatives on macroscopic
parameters as compared with a negative control, suggesting
that the action of the triazoles may be related to the
photosynthetic process. Borgati et al.18 evaluated triazolic
The phytotoxicity of a compound is directly related
to its antiproliferative activity.32 This relationship can be
visualized through microscopic analysis and cell cycle
evaluation of the meristematic cells. In the present study, the
mitotic index (MI) was evaluated, as well as the frequencies
of chromosomal alteration (CA) and nuclear alteration
(NA). The MI was reduced in the meristematic cells of
lettuce roots treated with 4a (100, 500 and 1000 μg mL–1),
4b (1000 μg mL–1), 4c (1000 μg mL–1), 4d (500 and
1000 μg mL–1), 4e (500 and 1000 μg mL–1), 4f (100, 500
and 1000 μg mL–1), and 4h (500 and 1000 μg mL–1), with
the last compound being the most repressive, resulting in
an MI reduction of 46.27% relative to the control (water)
value. The MI reduction is an indication of events blocking

Vol. 00, No. 00, 2019
Costa et al.
7
Table 1. Macroscopic and microscopic parameters evaluated in Lactuca sativa seeds and root meristems treated with triazoles 4a-4i at five different
concentrations. The positive control was the herbicide picloram, whereas the negative controls were distilled water and dichloromethane (DCM)
Concentration /
(μg mL-1)
Compound
G / %
GSI
RG
IM / %
NA / %
CA / %
1000
93ab
92ab
97ab
98ab
99ab
80
7.66
7.88
9.39
7.13
8.82
1.77
2.7333
3.03
500
9.38
0.97ab
0.57ab
0.50ab
0.27ab
1.03ab
0.56ab
0.67ab
0.53ab
0.27ab
1.16b
4a
100
10.80ab
11.56ab
10.74ab
6.34
13.40ab
12.83ab
12.46ab
4.51
8.92
2.4633
10
12.44ab
14.67
8.34
3.69
1
1000
500
100
10
3.1
2.1667
90ab
97ab
95ab
98ab
65c
7.25
5.18
10.96ab
12.69ab
12.04ab
14.15
7.35
2.4633
4b
4c
4d
4e
4f
10.46b
11.03ab
11.42ab
3.81c
9.63
2.9633
11.37ab
11.58ab
1.85c
2.8367
1
2.3267
1000
500
100
10
1.8333b
2.1333
90ab
97ab
96ab
98ab
86
7.26
4.55
9.51a
10.30ab
13.40
16.13
6.07
1.20b
10.60ab
10.86ab
11.57ab
5.73
6.88
0.90ab
0.27ab
0.10ab
1.27b
1.7267b
1.5333bc
1.7667b
1.3667abc
2.3233
9.65
1
13.68b
3.23
1000
500
100
10
89ab
96ab
98ab
97ab
100ab
95ab
97ab
97ab
99ab
87
7.57
4.69
10.08ab
11.96ab
14.39
18.06
9.53a
12.46ab
12.89ab
13.73
15.03
7.24
0.80ab
0.43ab
0.17ab
0.00ab
0.30ab
0.20ab
0.00ab
0.30ab
0.10ab
0.00ab
0.00ab
0.00ab
0.00ab
0.00ab
0.23ab
0.07ab
0.00ab
0.07ab
0.00ab
0.37ab
0.86ab
0.33ab
0.00ab
0.00ab
0.00ab
0.00ab
0.00ab
0.00ab
0.00ab
0.33a
10.54b
11.38ab
10.81ab
11.02ab
11.10ab
11.67ab
10.97ab
11.71ab
6.65
6.95
1.9967
9.68
1.8967b
2.2333
1
11.71ab
15.40
15.79
13.77b
13.36ab
12.67ab
4.65
1000
500
100
10
1.7333b
1.6667b
1.5333bc
1.1667abc
0.9333abc
0.7667abc
0.6333abc
1.0633abc
1.2933abc
1.3633abc
0.7333abc
0.6333abc
0.6633abc
0.7333abc
0.6667abc
0.4033abc
0.6633abc
0.9933abc
0.6667abc
1.2333abc
1.3667abc
1.1667abc
1.1533abc
1.2abc
1
1000
500
100
10
92ab
97ab
98ab
97ab
97ab
96ab
98ab
99ab
100ab
96ab
98ab
97ab
98ab
97ab
97ab
100ab
100ab
99ab
98ab
99a
6.81
4.75
8.49
10.65ab
11.73ab
12.02ab
11.04ab
10.97ab
11.37ab
11.88ab
12.18ab
8.73
6.93
10.57ab
14.46
16.92
8.70
10.39a
11.19a
8.56
1
1000
500
100
10
9.34
9.17
4g
4h
10.05
11.53ab
12.61ab
6.53
8.68
10.78ab
13.83
6.05
1
1000
500
100
10
9.28
7.58
7.14
11.20ab
12.04ab
11.64ab
11.29ab
12.08ab
11.71ab
12.09ab
12.09ab
12.33a
12.11b
3.63c
9.13
11.66ab
13.04b
15.22
10.79ab
13.60
16.10
17.43
17.58
11.26a
11.56b
3.73c
11.97ab
11.87ab
11.76ab
12.29ab
12.43ab
12.66ab
13.28ab
11.85a
13.01b
0.46c
1
1000
500
100
10
4i
1
0.9667abc
0.5333a
1.1b
H2O
DCM
picloram (1000)
Control
100b
67c
0.57b
7.27c
0.7333c
G: percentage of germination; GSI: germination speed index; RG: root growth; MI: mitotic index; NA: frequency of nuclear alterations; CA: frequency
of chromosomal alterations; DCM: dichloromethane. Means followed by the letter a represent water; means followed by the letter b represent DCM; and
means followed by the letter c represent picloram; according to Dunnet’s test (p < 0.05).

8
Synthesis of Glycerol-Derived 4-Alkyl-Substituted 1,2,3-Triazoles
J. Braz. Chem. Soc.
cell division, such as the death of the nucleus rendering
the initiation of prophase and consequently cell division
difficult.44,46
by compounds 4f-4i was similar to that by both controls
(positive and negative) (Table 1). The results were similar
to those found in the investigation by Bernardes et al.,47
in which the CA frequency was high after exposure of
the seeds to difenoconazole, where broken chromosomes,
C-metaphase cells, anaphase bridges, and polyploid
metaphases were observed. In the present study, we also
detected non-oriented, sticky, and delayed chromosomes,
C-metaphase cells, and anaphase bridges (Figures 2 and 3).
All the evaluated compounds induced CAs (Figure 2),
demonstrating an increasing effect with an increase in the
compound concentration. The sticky chromosomes were
the most expressive variable (Figure 3). This alteration may
be related to the mechanism of aneugenic action caused by
the interference of the triazole molecules with the mitotic
spindle fibers, which impairs the chromosomal organization
during metaphase and subsequently cell division, resulting
in the daughter cells being different from the mother cell.48-50
Additionally, the presence of bridges, classified as a
clastogenic alteration, was observed. These changes occur
as a result of the breakdown of chromosomal end points,
where the chromosomes consequently lose their stability.
Thus, they bind to other chromosomes, giving rise to
dicentric chromosomes that are pulled during segregation,
forming a bridge between the cell poles.51,52
At the highest concentration, the triazoles promoted
a reduction of dividing cells in lettuce root meristems.
However, at lower concentrations, an increase in the
percentage of dividing cells was observed compared with
that in the controls (Table 1). Compounds 4a (1 μg mL–1),
4b (1 μg mL–1), 4c (1 and 10 μg mL–1), 4d (1 and
10 μg mL−1), 4e (1 and 10 μg mL–1), 4f (1 and 10 μg mL–1),
4g (1 μg mL–1), 4h (1 μg mL–1), and 4i (1, 10, 100, and
500 μg mL–1) positively influenced cell proliferation, with
compound 4i especially resulting in a 56.12% increase of
such activity.
An MI increase means that the number of cells
undergoing mitotic division is increasing. If this increase is
accompanied by an increase in the NA and CA percentages,
it demonstrates chemical compound toxicity. Consequently,
the daughter cells from these divisions will present
alterations that may cause cell death and/or compromise
the genetic integrity of subsequent generations of cells
originating from these altered mother cells.37
With regard to the NAs (Table 1), only compound 4a at
1000 μg mL–1 showed a significant difference in frequency
in relation to the controls. The other triazoles and treatments
showed statistically similar frequencies to those of the
respective negative controls (water and DCM).
From the analyzed chromosomal changes, it is possible
to infer the action mechanism of these triazoles; that is,
it is related to the malfunction or non-polymerization of
the mitotic spindle, as reported in the investigation by
For the CAs, there was a high frequency generated
by compounds 4a-4e, whereas the frequency generated
Figure 2. Chromosomal alterations (non-oriented-C, sticky, C-metaphase, bridge, and delay) observed in root meristematic cells of L. sativa exposed to
the triazoles 4a-4i.

Vol. 00, No. 00, 2019
Costa et al.
9
complete inactivation of the cellular mitotic spindle, where
no equatorial plate is mounted, consequently leading to the
interruption of cell division54 and reinforcing the aneugenic
mechanism of action of the triazoles.
The inhibitory activities of compounds 4a-4i toward the
mycelial growth and sporulation of C. gloeosporioides are
depicted in Table 2, along with regression models. All the
triazoles investigated herein displayed inhibitory effects
on C. gloesporioides growth in a dose-dependent manner.
Compounds 4a-4i showed a lower efficiency in
inhibiting mycelial growth than the positive control
tebuconazole, a commercial fungicide. As can be seen in
Table 2, compounds 4d and 4i were the most active (ED50
values below 20 ppm), with 4i being the derivative with
the highest potency (ED50 10.14 ppm).
With regard to the inhibition of sporulation, all the
4-alkyl-substituted triazoles displayed considerable
inhibitory effects (ED50) that were comparable to that of
tebuconazole. In particular, 4e was the most active, with
an ED50 value lower than 0.00002 ppm.
Figure 3. Chromosomal abnormalities observed in root meristematic
cells of L. sativa exposed to the triazoles 4a-4i. (a) Sticky chromosome,
(b) c-metaphase, (c) anaphase bridge, and (d) non-oriented chromosome.
Scale bar = 10 μm.
Costa et al.32 Depolymerizing substances are capable of
inducing severe damage in the process of cell division,
resulting in genetic alterations, which is classified as an
aneugenic action.53
One of the significant alterations observed in this work
was the presence of C-metaphase. This is caused by the
On the basis of the ED50 values of the compounds
(Table 2), it was possible to group them into different
fungicidal classes. The group related to the efficiency
of the compounds demonstrated the fungicidal action of
the treatments. Similarly, the group related to sensitivity
Table 2. Mean mycelial growth and sporulation values of C. gloeosporioides treated with compounds 4a-4i, and regression models
Mycelial growth
Sporulation
Compound
ED50
/
ED100
ppm
/
Effectiveness Sensitivity
ED50
ppm
/
ED100
ppm
/
Effectiveness Sensitivity
Regression equation
Regression equation
ppm
(E)
(S)
(E)
(S)
Ŷ = 21.679 + 0.043x**
Ŷ = 5.325 + 0.408 logx**
4a
661.69 1829.91
471.86 1100.37
NE
NS
0.16
0.29
0.29
0.64
1023.94
1016.99
800.18
400.09
HE
HS
R2 = 0.99
R2 = 0.94
Ŷ = 12.462 + 0.079x**
Ŷ = 5.231 + 0.429 logx**
4b
NE
NE
LE
NE
LE
NE
LE
LE
HE
NS
NS
LS
NS
LS
NS
LS
LS
HS
HE
HE
HE
HE
HE
HE
HE
HE
HE
HS
HS
HS
HS
HS
HS
HS
HS
HS
R2 = 0.99
R2 = 0.87
Ŷ = 7.552 + 0.167 − 7.509.10−5x2**
Ŷ = 5.298 + 0.567 logx**
4c
290.58
18.14
981.09
414.17
R2 = 0.99
R2 = 0.95
Ŷ = 3.588 + 1.214logx*
Ŷ = 5.147 + 0.769 logx**
4d
R2 = 0.79
R2 = 0.93
Ŷ = 19.307 + 0.0312x*
Ŷ = 5.930 + 0.193 logx**
4e
984.07 2587.15
0.0002 1268.59
R2 = 0.70
R2 = 0.99
Ŷ = 3.359 + 1.243logx*
Ŷ = 5.450 + 0.642 logx**
4f
20.83
393.79
0.20
0.01
0.49
0.07
< 1
390.79
1234.53
556.78
568.89
13.71
R2 = 0.75
R2 = 0.94
Ŷ = 27.934 + 0.069x*
Ŷ = 5.548 + 0.298 logx**
4g
319.79 1044.53
R2 = 0.69
R2 = 0.95
Ŷ = 5.153 − 0.684x*
Ŷ = 5.215 + 0.701 logx**
4h
25.71
10.14
0.26
858.59
965.8
35.32
R2 = 0.72
R2 = 0.91
Ŷ = 48.709 + 0.133x − 8.269x2*
Ŷ = 5.718 + 0.636 logx**
4i
R2 = 0.77
R2 = 0.95
Ŷ = 5.627 + 1.097 logxns
Ŷ = 6.598 + 0.640 logx2**
Tebuconazole
R2 = 0.55
R2 = 0.99
ED50: concentration of the active ingredient of the fungicide necessary to inhibit 50% of the mycelial growth and sporulation of the pathogen; ED100: concentration of the active
ingredient of the fungicide necessary to inhibit 100% of the mycelial growth and sporulation of the pathogen; E: effectiveness of fungicides; NE: not efficient; LE: low efficiency;
HE: high efficiency; S: sensitivity of C. gloeosporioides to fungicides; NS: not sensitive; LS: low sensitivity; HS: high sensitivity; R2: coefficient of determination. Regression
coefficient followed by * or ** are significant at the 5 or 1% probability, respectively; ns: not significant.

10
Synthesis of Glycerol-Derived 4-Alkyl-Substituted 1,2,3-Triazoles
J. Braz. Chem. Soc.
allowed inference of the pathogenic resistance of
C. gloeosporioides to the stress caused by the fungicides.
In terms of mycelial growth, three distinct groups
could be distinguished; namely, high efficiency (HE), low
efficiency (LE), and not efficient (NE). As expected, the
activity of tebuconazole fell into the HE group. Even though
compounds 4d and 4i were the most active, they were
included in the LE group (along with compounds 4f and 4h)
because their activity was ca. 70 times (compound 4d) and
39 times (compound 4i) lower than that of tebuconazole.
The triazoles 4a, 4b, 4c, 4e, and 4g fell in to the NE group.
With regard to the inhibitory effects on sporulation,
tebuconazole and derivatives 4a-4i were highly efficient
and formed the only HE group in Table 2.
The evaluation based on phenotypic expression is
linked to the sensitivity of C. gloeosporioides to the studied
compounds. The analysis of ED50 values for inhibition of
mycelial growth also resulted in the identification of three
distinct groups (HS: high sensitivity; LS: low sensitivity;
NS: not sensitive). C. gloeosporioides was considered to
be highly sensitive to the standard control tebuconazole
only. However, in terms of the inhibition of sporulation,
the fungus was highly sensitive to all the compounds
investigated (Table 2), where there was no difference in
the classification of treatments 4a-4i in relation to the
tebuconazole control (all classified as HS). The ED50
values within this group ranged between 0.00002 (4e) and
0.64 ppm (4d) for the triazolic derivatives.
The variations in the efficiency of the triazoles and
the sensitivity of the fungal isolate to these derivatives,
as observed in the present investigation, can be explained
by the interaction of the molecules with their target site of
action on the fungal species. Several factors can prevent the
fungicide from reaching the target. Using Botrytis cinerea
as a model, Kretschmer et al.55 demonstrated that the
main mechanisms used by the fungus in response to
fungicidal stress were alteration of the target site, fungicide
detoxification, over expression of the target protein
triggered by fungicide accumulation in the cell, and efflux
of the fungicide from the target site.
gene could reduce the affinity of the triazoles to their target
site of action on the fungal cell, or the over expression of
CYP51 could increase the levels of sterol 14α-demethylase
in the fungus.
Another hypothesis, which does not exclude the
former one, may be linked to an increase of triazole efflux
due to positive regulation of the adenosine triphosphate
(ATP)-binding cassette or major facilitator super family
transporters in the membrane.57
Conclusions
By using the CuAAC reaction as the key step and
glycerol as a starting material, a series of nine glycerol-
derived 4-alkyl-substituted 1,2,3-triazoles were synthesized
in good yields and fully characterized. Compared with the
commercial fungicide tebuconazole, all the compounds
evaluated were highly efficient in inhibiting the sporulation
of C. gloeosporioides, with ED50 values lower than
1 mg L−1. In addition, all the derivatives tested demonstrated
aneugenic and clastogenic actions on meristematic cells
of L. sativa roots. These glycerol-derived 1,2,3-triazoles
may thus represent a novel scaffold to be exploited for the
development of new active ingredients for fungus control.
Supplementary Information
Supplementary information IR, NMR (1H and 13C) and
MS spectra of the compounds is available free of charge at
http://jbcs.sbq.org.br as PDF file.
Acknowledgments
The authors are grateful to the following Brazilian
agencies: Fundação de Amparo à Pesquisa e Inovação
do Espírito Santo (FAPES), Conselho Nacional de
Desenvolvimento Científico e Tecnológico (CNPq) and
Coordenação de Aperfeiçoamento de Pessoal de Nível
Superior (CAPES).
A hypothesis that explains the variations in efficiency
of the triazoles and the sensitivity of C. gloeosporioides
in this work may involve the inhibition of the enzyme
lanosterol 14α-demethylase (CYP51). The triazoles are
able to fit into the active site of CYP51 through hydrophobic
interactions, hydrogen bonding, and π-π stacking with
the sextet binder of the heme group of the enzyme. As
a result, the amount of ergosterol decreases and the
accumulation of 14α-demethylated sterols occurs, which
disrupts the membrane structure and causes the death of
the phytopathogen.56 Therefore, changes in the CYP51
References
1. Arora, P.; Arora, V.; Lamba, H. S.; Wadhwa, D.; Int. J. Pharm.
Sci. Res. 2012, 3, 2947.
2. Quin, L. D.; Tyrell, J. A.; Fundamentals of Heterocyclic
Chemistry: Importance in Nature and in the Synthesis of
Pharmaceuticals; John Willey & Sons, Inc.: New Jersey, 2010.
3. Lamberth, C.; Pest Manage. Sci. 2013, 69, 1106.
4. Lopes, S. M. M.; Novais, J. S.; Costa, D. C. S.; Castro, H. C.;
Figueiredo, M. S.; Ferreira, V. F.; Pinho e Melo, T. M. V. D.;
Silva, F. C.; Eur. J. Med. Chem. 2018, 13, 1010.

Vol. 00, No. 00, 2019
Costa et al.
11
24. https://www.chemicalsafetyfacts.org/glycerol/ accessed in
October 2019.
5. López-Rojas, P.; Janeczko, M.; Kubinski, K.; Amesty,
A.; Mastyk, M.; Estévez-Braun, A.; Molecules 2018, 23,
199.
25. Vivek, N.; Sindhu, R.; Madhavan, A.; Anju, A. J.; Castro, E.;
Faraco, V.; Pandey, A.; Binod, P.; Bioresour. Technol. 2017,
239, 507.
6. Sajja, Y.; Vonguru, S.; Jilla, L.; Vulupala, H. R.; Bantu, R.;
Yogeswari, P.; Sriram, D.; Nagarapu, L.; Bioorg. Med. Chem.
Lett. 2016, 26, 4292.
26. Anitha, M.; Kamarudin, S. K.; Kofli, N. T.; Chem. Eng. J. 2016,
295, 119.
7. Tan, W.; Li, Q.; Wang, H.; Liu, Y.; Zhang, J.; Dong, F.; Guo,
Z.; Carbohydr. Polym. 2016, 142, 1.
27. Bagheri, S.; Julkapli, N. M.; Yehye, W. A.; Renewable
Sustainable Energy Rev. 2015, 41, 113.
8. Shaikh, M. H.; Subhedara, D. D.; Khanb, F.A. K.; Sangshettib,
J. N.; Shingatea, B. B.; Chin. Chem. Lett. 2016, 27, 295.
9. Petrova, K. T.; Potewar, T. M.; da-Silva, P. C.; Barros, M. T.;
Calhelha, R. C.; Ćiric, A.; Soković, M.; Ferreira, I. C. F. R.;
Carbohydr. Res. 2015, 417, 66.
28. Mota, C. J.A.; da Silva, C. X.A.; Gonçalves, L. C.; Quim. Nova
2009, 32, 639.
29. García, J. I.; García-Marína, H.; Piresa, E.; Green Chem. 2010,
12, 426.
30. Gu, J.; Jérôme, F.; Green Chem. 2010, 12, 1127.
31. Ouyang, Y.; Yang, H.; Zhang, P.; Wang, Y.; Kaur, Y.; Zhu, Z.;
Wang, Z.; Sun,Y.; Hong, W.; Ngeow,Y. F.; Wang, H.; Molecules
2017, 22, 1592.
10. Yamada, M.; Takahashi, T.; Hasegawa, M.; Matsumura, M.;
Ono, K.; Fujimoto, R.; Kitamura, Y.; Murata, Y.; Kakusawa,
N.; Tanaka, M.; Obata, T.; Fujiwara, Y.; Yasuike, S.; Bioorg.
Med. Chem. Lett. 2018, 28, 152.
32. Costa, A. V.; de Oliveira, M. V. L.; Pinto, R. T.; Moreira, L. C.;
Gomes, E. M. C.; deAssisAlves, T.; Pinheiro, P. F.; de Queiroz,
V. T.;Vieira, L. F.A.; Teixeira, R. R.; Júnior, W. C. J.; Molecules
2017, 22, 1666.
11. da Silva, F. C.; de Souza, M. C. B.V.; Frugulhetti, I. I. P.; Castro,
H. C.; Souza, S. L. O.; de Souza, T. M. L.; Rodrigues, D. Q.;
Souza, A. M. T.; Abreu, P. A.; Passamani, F.; Rodrigues, C. R.;
Ferreira, V. F.; Eur. J. Med. Chem. 2009, 44, 373.
12. Jordão, A. K.; Ferreira, V. F.; Souza, T. M. L.; Faria, G. G. S.;
Machado, V.; Abrantes, J. L.; Souza, M. C. B. V.; Cunha, A.
C.; Med. Chem. 2011, 19, 1860.
33. Barbosa, L. C. A.; Pereira, U. A.; Maltha, C. R. A.; Teixeira,
R. R.; Valente, V. M. M.; Ferreira, J. R. O.; Costa-Lotufo, L.
V.; Moraes, M. O.; Pessoa, C.; Molecules 2010, 15, 5629.
34. Lima, L. S.; Barbosa, L. C. A.; de Alvarenga, E. S.; Demuner,
A. J.; da Silva, A. A.; Aust. J. Chem. 2003, 56, 625.
35. Raja, M. R. C.; Velappan, A. B.; Chellappan, D.; Debnath, J.;
Mahapatra, S. K.; Eur. J. Med. Chem. 2017, 139, 503.
36. Matoba, H.; Mizutani, T.; Nagano, K.; Hoshi, Y.; Uchiyama,
H.; Hereditas 2007, 144, 235.
13. Devender, N.; Gunjan, S.; Chhabra, S.; Singh, K.; Pasam,V. R.;
Shukla, S. K.; Sharma, A.; Jaiswal, S.; Singh, S. K.; Kumar,Y.;
Lal, J.; Trivedi, A. K.; Tripathi, R.; Tripathi, R. P.; Eur. J. Med.
Chem. 2016, 109, 187.
14. Kumar, A.; Paliwal, D.; Saini, D.; Thakur, A.; Aggarwal, S.;
Kaushik, D.; Eur. J. Med. Chem. 2014, 85, 147.
15. Teixeira, R. R.; Gazolla, P. A. R.; da Silva, A. M.; Borsodi, M.
P. G.; Bergmann, B. R.; Ferreira, R. S.;Vaz, B. G.;Vasconcelos,
G. A.; Lima, W. P.; Eur. J. Med. Chem. 2018, 146, 274.
16. Kamal,A.; Shankaraiah, N.; Devaiah,V.; Reddy, K. L.; Juvekar,
A.; Sen, S.; Kurian, N.; Zingde, S.; Bioorg. Med. Chem. Lett.
2008, 18, 1468.
37. Pinheiro, P. F.; Costa,A.V.;Alves, T.A.; Galter, I. N.; Pinheiro,
C. A.; Pereira, A. F.; Oliveira, C. M. R.; Praça-Fontes, M. M.;
J. Agric. Food Chem. 2015, 63, 8981.
th ed.;
38. Montgomery, D. C.; Design and Analysis of Experiments, 5
John Wiley: New York, 2001.
39. Cruz, C. D.; Acta Sci., Agron. 2013, 35, 271.
17. Colombano, G.; Traveli, C.; Galli, U.; Caldarelli, A.; Chini,
M. G.; Canonico, P. L.; Sorba, G.; Bifulco, G.; Tron, G. C.;
Genazzani, A. A.; J. Med. Chem. 2010, 53, 616.
18. Borgati, T. F.; Alves, R. B.; Teixeira, R. R.; de Freitas, R. P.;
Perdigão, T. G.; da Silva, S. F.; dos Santos, A. P.; Bastidas, A.
J. O.; J. Braz. Chem. Soc. 2013, 24, 953.
40. Edgington, L. V.; Khew, K. L.; Barron, G. L.; Phytopathology
1971, 61, 42.
41. Rampersad, S. N.; Teelucksingh, L. D.; Plant Dis. 2012, 96,
1526.
42. R CORE TEAM-A Language and Environment for Statistical
Computing; R Foundation for Statistical Computing, Vienna,
2016. Available at http://www.R-project.org/ accessed in
October 2019.
19. Agalave, S. G.; Maujan, S. R.; Pore,V. S.; Chem. - Asian J. 2011,
6, 2696.
20. Dheer, D.; Singh, V.; Shankar, R.; Bioorg. Chem. 2017, 71, 30.
21. Struthers, H.; Mindt, T. L.; Schibli, R.; Dalton Trans. 2010, 39,
675.
43. Aragão, F. B.; Andrade-Vieira, L. F.; Ferreira, A.; Costa, A.V.;
Queiroz, V. T.; Pinheiro, P. F.; Allelopathy J. 2015, 35, 259.
44. Aragão, F. B.; Queiroz,V. T.; Ferreira,A.; Costa,A.V.; Pinheiro,
P. F.; Carrijio, T. T.;Andrade-Vieira, L. F.; Rev. Biol. Trop. 2017,
65, 435.
22. Peiter, G. C.;Alves, H. J.; Sequinel, R.; Bautitz, I. R.; Rev. Bras.
Energ. Renov. 2016, 5, 519.
23. Beatriz, A.; Araújo,Y. J. K.; de Lima, D. P.; Quim. Nova 2011,
34, 306.
45. Taiz, L.; Zeiger, E.; Fisiologia Vegetal, 5a
ed.; Artmed: Porto
Alegre, 2013.

12
Synthesis of Glycerol-Derived 4-Alkyl-Substituted 1,2,3-Triazoles
J. Braz. Chem. Soc.
46. Sousa, S. M.; Viccini, L. F.; Braz. J. Pharmacog. 2011, 21, 98.
52. Campos, J. M. S.; Davide, L. C.; Soares, G. L. G.; Viccini, L.
F.; Allelopathy J. 2008, 1, 143.
47. Bernardes, P. M.;Andrade-Vieira, L. F.;Aragão, F. B.; Ferreira,
A.; Ferreira, M. F. S.; Water, Air, Soil Pollut. 2015, 226, 207.
48. Andrade-Vieira, L. F. In Landfills:Waste Management, Regional
Practices and Environmental Impacts, 1st ed.; Cabral, G. B. C.;
Botelho, B. A. E., eds.; Nova Science Publishers: New York,
2012, p. 319.
53. Santos, F. E.; Carvalho, M. S. S.; Silveira, G. L.; Correa1, F. F.;
Cardoso, M. G.; Andrade-Vieira, L. F.; Vilela, L. R.; Environ.
Sci. Pollut. Res. 2018, 25, 1.
54. Fernandes, T. C. C.; Mazzeo, D. E. C.; Marin-Morales, M. A.;
Ecotoxicol. Environ. Saf. 2009, 72, 1680.
49. Andrade-Vieira, L. F.; Palmieri, L. J.; Botelho, C. M.; Luber,
J.; Silva, M. F. F.; S. Afr. J. Bot. 2017, 113, 443.
50. Alves, T. A.; Pinheiro, P. F.; Praça-Fontes, M. M.; Andrade-
Vieira, L. F.; Corrêa, K. B.;Alves, T.A.; da Cruz, F.A.; Lacerda
Jr,V.; Ferreira,A.; Soares, T. C. B.; Ind. Crops Prod. 2018, 114,
59.
55. Kretschmer, M.; Leroch, M.; Mosbach,A.;Walker,A.; Fillinger,
S.; Mernke, D.; Schoonbeek, H.; Pradier, J.; Leroux, P.; Waard,
M.; Hahn, M.; PLoS Pathog. 2009, 5, 12.
56. Price, C. L.; Parker, J. E.; Warrilow, G. S.; Kelly, D. E.; Kelly,
S. L.; Pest Manage. Sci. 2015, 71, 1054.
57. Lerroux, P.; Walker, A. S.; Pest. Manage. Sci. 2011, 67, 44.
51. EL-Ghamery, A. A.; EL-Kholy, M. A.; EL-Yousser, M. A. A.;
Mutat. Res. 2003, 53, 29.
Submitted: June 21, 2019
Published online: October 16, 2019
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