Novel ester derivative of cinnamates with different long alkoxy chain: synthesis, mesomorphic properties, biological evaluation

Article abstract of DOI:10.1080/15421406.2021.1905140

A novel series of liquid crystals involving cinnamate-based mesogenic units interlinked between aromatic ester and alkyl bromide were designed and synthesized. All target molecules were confirmed by IR, ¹H NMR, ¹³C NMR, ESI-MS, and elemental analysis. The mesomorphic behavior of novel synthesized materials (P1–P18), (V1–V18), and (M1–M18) was investigated through a polarizing optical microscope, differential scanning calorimetry, and thermogravimetric analysis (TGA) analysis. The lower carbon chain substituted member showed nematic phase while compound possess higher carbon chain exhibited only SmC phase. Thermal stability is determined by TGA analysis. All the cinnamate derivatives were screened for their anti-microbial, anti-malarial, and anti-tuberculosis potency. Among them, most of the derivatives exhibited outstanding anti-bacterial and anti-tuberculosis activity. Some derivatives also exhibited potent anti-fungal activity.

Full text of DOI:10.1080/15421406.2021.1905140

Molecular Crystals and Liquid Crystals
ISSN: (Print) (Online) Journal homepage: https://www.tandfonline.com/loi/gmcl20
Novel ester derivative of cinnamates with
different long alkoxy chain: synthesis,
mesomorphic properties, biological evaluation
Pradip C. Bhalodiya, Hemant N. Patel, Tejasvi H. Parmar, Chetan B. Sangani
& Dhanji P. Rajani
To cite this article: Pradip C. Bhalodiya, Hemant N. Patel, Tejasvi H. Parmar, Chetan B. Sangani
& Dhanji P. Rajani (2021): Novel ester derivative of cinnamates with different long alkoxy chain:
synthesis, mesomorphic properties, biological evaluation, Molecular Crystals and Liquid Crystals,
DOI: 10.1080/15421406.2021.1905140
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MOLECULAR CRYSTALS AND LIQUID CRYSTALS
https://doi.org/10.1080/15421406.2021.1905140
Novel ester derivative of cinnamates with different long
alkoxy chain: synthesis, mesomorphic properties,
biological evaluation
Pradip C. Bhalodiyaa, Hemant N. Patela, Tejasvi H. Parmara, Chetan B. Sangania,
and Dhanji P. Rajanib
aDepartment of Chemistry, Shri M.M Patel Institute of Sciences and Research, Kadi Sarva
b
Vishwavidyalaya, Gandhinagar, Gujarat 382016, India; Microcare Laboratory and TRC, Surat,
Gujarat, India
KEYWORDS
ABSTRACT
Anti-malarial; anti-microbial;
anti-tuberculosis; cinna-
mates LCs; nematic; smectic
A novel series of liquid crystals involving cinnamate-based meso-
genic units interlinked between aromatic ester and alkyl bromide
were designed and synthesized. All target molecules were confirmed
1
by IR, H NMR, 13C NMR, ESI-MS, and elemental analysis. The meso-
morphic behavior of novel synthesized materials (P1–P18),
(V1–V18), and (M1–M18) was investigated through a polarizing
optical microscope, differential scanning calorimetry, and thermogra-
vimetric analysis (TGA) analysis. The lower carbon chain substituted
member showed nematic phase while compound possess higher car-
bon chain exhibited only SmC phase. Thermal stability is determined
by TGA analysis. All the cinnamate derivatives were screened for
their anti-microbial, anti-malarial, and anti-tuberculosis potency.
Among them, most of the derivatives exhibited outstanding anti-bac-
terial and anti-tuberculosis activity. Some derivatives also exhibited
potent anti-fungal activity.
1. Introduction
Liquid crystalline (LC) state study of novel materials is becoming a multidisciplinary
area and it is beneficial to mankind and other industrial applications through technolo-
gists [1–4] because of its exceptional property to flow as liquid and optical properties as
crystals. Investigation of LC state is intentional with an interpretation to comprehend
and establish the consequence of molecular structure on LC properties [5, 6] as a sig-
nificance of molecular rigidity and flexibility [7, 8]. Liquid crystal can be characterized
into lyotropic, thermotropic, and metallotropic phases. Lyotropic and thermotropic
liquid crystals contain typically of organic compounds although few minerals are
reported too [9]. Liquid crystals in the nematic cluster are most extensively used in the
construction of liquid crystal displays (LCD) principally due to their exceptional phys-
ical properties as well as varied temperature range. Moreover, the nematic phase which
CONTACT Hemant N. Patel
hemant_2patel@yahoo.co.in or hemantn2patel@gmail.com
Department of Chemistry,
Shri M.M Patel Institute of Sciences and Research, Kadi Sarva Vishwavidyalaya, Gandhinagar 382016, Gujarat, India.
Supplemental data for this article is available online at https://doi.org/10.1080/15421406.2021.1905140.
ß 2021 Taylor & Francis Group, LLC

2
P. C. BHALODIYA ET AL.
is generally observed in liquid crystal by orientation of molecules on average surface
with specific direction. By smearing an electric or magnetic field, the orientation of the
molecules can be derived in a feasible approach [10]. Literature survey revealed that the
chalcone- or cinnamic acid-based esters have been widely used for the preparation of
different types of liquid crystalline compounds, respectively [11–15].
Doshi and coworkers have investigated molecular structure of LC property of chal-
conyl ester-based homologous series [16–18]. Sharma and coworkers also demonstrated
the isomeric and nonisomeric homologues series with chalconyl ester linkage group
[19–23]. In addition, homologues series based on two phenyl ring and one central chal-
cone linkage group was also reported [24]. Moreover, occurrence of P-bond conjuga-
tion in a, b-unsaturated ketone leads to a good charge transfer axis and the aromatic
rings, act as a tool for a donor and an acceptor [25].
A wide range of chalcone derivatives were reported to display a broad spectrum of
antimalarial [26], antibacterial [27], inflammatory [28], antifungal [29], antiulcer [30],
anticancer [31], anti-tubercular [32] activities. The presence of a, b-unsaturated car-
bonyl group in chalcone (-CH ¼ CH-CO-) was accountable for anti-microbial activity,
which can be transformed liable upon the type of substituent present on the aromatic
rings [33]. Therefore, the determination of the work to prepared and studied the effect
of cinnamate linkage group as well as effect of changeable alkyl spacer on mesomor-
phism and biological activities.
The broad literature investigation reveals that the di-ester of cinnamate derivative
with varied alkoxy side chain as liquid crystalline compounds are very rarely reported.
In this present study, we are going to report newly functionalized (E)-4-(3-(2-bromoe-
thoxy)-3-oxoprop-1-en-1-yl)phenyl,
(E)-4-(3-(2-methoxyethoxy)-3-oxoprop-1-en-1-
yl)phenyl and (E)-4-(3-(2-(2-methoxyethoxy)ethoxy)-3-oxoprop-1-en-1-yl)phenyl were
substituted with different alkoxy side chain and evaluated for their liquid crystalline
properties as well as biological activities (Scheme 1). In this study, we have investigated
total of 36 novel derivatives (P1–P18), (V1–V18), and (M1–M18) having diverse alkoxy
side chain (C1 to C18).
2. Experimental
2.1. Materials and methods
All chemicals of the highest purity were purchased from commercial sources and used
as received. The progress of the reaction was monitored by thin layer chromatography
(TLC) analysis on Merck pre-coated silica gel 60 F254 aluminum sheets, visualized by
UV light. Melting points were measured on an Optimelt MPA 100 melting point appar-
atus and are uncorrected. Fourier transform infrared spectroscopy (FTIR) spectra were
1
recorded on a Perkin Elmer FT-IR 377 spectrometer using KBr. H-NMR spectra were
recorded on Bruker AV 400 MHz spectrometer using CDCl3 as solvent and TMS as the
internal reference. 13C-NMR was recorded on a Bruker AV 100 MHz spectrometer using
DMSO as solvent. Mass spectra were recorded at Advion expression CMS, USA.
Acetone was used as the mobile phase, and electron spray ionization (ESI) was used as
the ion source. Elemental analysis was performed on Perkin-Elmer PE 2400 CHNS ana-
lyser. The mesophase type was identified by visual comparison with known phase

MOLECULAR CRYSTALS AND LIQUID CRYSTALS
3
Scheme 1. Synthetic route of preparation of derivatives (P1–P18), (V1–V18), and (M1–M18).
standards using a Nikon Eclipse LV-100 POL polarizing optical microscope (POM) fit-
ted with a hot stage temperature-controlled LTSE 420 heating stage (Linkam Scientific
Instruments, Tadworth, Surrey, UK) with temperature controlling accuracy of 0.1 K.
The transition temperatures and associated enthalpy changes were determined by differ-
ential scanning calorimeter (DSC) under nitrogen atmosphere. Thermo gravimetric ana-
lysis (TGA) was performed using a Perkin Elmer-STA 6000 apparatus under high
purity nitrogen.
2.1.1. General method for the synthesis of 4-alkoxybenzoic acid (A1–A18)
To a stirred solution of 1-alkylbromide (90 mmol) and 4-hydroxybenzoic acid
(36.20 mmol) in ethanol (200 mL) was added KOH (72.40 mmol) followed by potassium
iodide (KI) (1.5 mmol). Reflux the reaction mixture for 12 h. After completion of the
reaction monitored by TLC, cool the reaction mixture at room temperature and treated
with aqueous HCl solution up to pH ¼ 1. The white precipitation was obtained, which
was filtered off and dried under vacuum to give 4-alkyloxybenzoic acid (A1–A18). All
the derivatives were used without further purification for the next step. All the products
were confirmed by ESI-MS analysis.
2.1.2. Method for preparation of (E)-3-(4-hydroxyphenyl)acrylic acid (2)
In a stirred solution of malonic acid (122.83 mmol) in pyridine was added p-hydroxy
benzaldehyde (1) (61.41 mmol) followed by catalytic amount of aniline (0.3 mL) and the
mixture was heated to 65 ꢀC for 8 h and then cooled to room temperature. Acidify

4
P. C. BHALODIYA ET AL.
reaction mixture with 2 N HCl solution. Obtained creamy precipitate was collected by
filtration and dried under reduced pressure to give (E)-3-(4-hydroxyphenyl)acrylic acid
(2) as off white solid. The product was confirmed by ESI-MS analysis.
2.1.3. Method for preparation of 2-bromoethyl (E)-2-bromoethyl 3-(4-hydroxypheny-
l)acrylate (4a)
To a stirred solution of (E)-3-(4-hydroxyphenyl)acrylic acid (2) (24.37 mmol) in TEA
(40 mL) was added 1,2-dibromoethane (3a) (48.73 mmol) and allowed to heat at 65 ꢀC
for 4 h. After completion of the reaction, the reaction mixture was poured in ice-cold
water and extracted with ethyl acetate. Organic layer dried over Na2SO4 and concen-
trated under reduce pressure to give crude product which was purified by column chro-
matography to give 2-bromoethyl (E)-3-(4-hydroxyphenyl) acrylate as off-white solid.
The product was confirmed by ESI-MS analysis.
2.1.4. Method for preparation of (E)-2-methoxyethyl 3-(4-hydroxyphenyl)acrylate (4b)
To a stirred solution of (E)-3-(4-hydroxyphenyl)acrylic acid (2) (1 mmol) in dry THF
(3.5 mL), cooled at 0 ꢀC under nitrogen atmosphere, were added triphenylphosphine
(1.1 mmol) and 2-methoxyethanol (3b) (1.0 mmol). After that, add diisopropyl azodicar-
boxylate (DIAD) (1.1 mmol) to the reaction mixture. The mixture was stirred at room
temperature for 8 h, then evaporated under vacuum, extracted with ethyl acetate, and
washed with NaHCO3 saturated solution. The collected organic phase was dried on
anhydrous Na2SO4, and evaporated under vacuum to get crude material, which was
purified by silica-gel column chromatography using ethyl acetate/n-Hexane mixture as
eluent. The product was confirmed by ESI-MS analysis.
2.1.5. Method for preparation of (E)-2-(2-methoxyethoxy)ethyl 3-(4-hydroxyphenyl)a-
crylate (4c)
To a stirred solution of (E)-3-(4-hydroxyphenyl)acrylic acid (2) (1 mmol) in dry THF
(3.5 mL), cooled at 0 ꢀC under nitrogen atmosphere, were added triphenylphosphine
(1.1 mmol) and 2-(2-methoxyethoxy)ethanol (3c) (1.0 mmol). After that, add diisopropyl
azodicarboxylate (DIAD) (1.1 mmol) to the reaction mixture. The mixture was stirred at
room temperature for 10 h, then evaporated under vacuum, extracted with ethyl acetate,
and washed with NaHCO3 saturated solution. The collected organic phase was dried on
anhydrous Na2SO4, and evaporated under vacuum to get crude material, which was
purified by silica-gel column chromatography using ethyl acetate/n-Hexane mixture as
eluent. All the product was confirmed by ESI-MS analysis.
2.1.6. General method for the synthesis of (E)-4-(3-(2-bromoethoxy)-3-oxoprop-1-en-
1-yl)phenyl 4-alkoxybenzoate (P1–P18)
To a stirred solution of 4-alkyloxybenzoic acid (A1–A18) (1 mmol) in dichloromethane
(DCM) (5 mL) was added 2-bromoethyl (E)-2-bromoethyl 3-(4-hydroxyphenyl)acrylate
(4a) (1.1 mmol). Further, N,N’-dicyclohexylcarbodiimide (DCC) (1.5 mmol) was added
to reaction mixture followed by 4-dimethylaminopyridine (DMAP) (0.05 mmol).

MOLECULAR CRYSTALS AND LIQUID CRYSTALS
5
Resulting solution stirred for 12–16 h at room temperature. After completion of the reaction
mixture, reaction mixture was filtered, filtrate was concentrated under vacuum to give crude
product which was purified column chromatography to give (E)-4-(3-(2-bromoethoxy)-3-
oxoprop-1-en-1-yl)phenyl 4-alkoxybenzoate (P1–P18) as white solid. All final compound
was purified by column chromatography by 60–120 mesh silica. (Elutes in 0% to 20% of
Ethyl acetate in Hexanes). TLC system (2:8, Ethyl acetate: Hexane).
2.1.7. General method for the synthesis of (E)-4-(3-(2-methoxyethoxy)-3-oxoprop-
1-en-1-yl)phenyl 4-alkoxybenzoate (V1–V18)
To a stirred solution of 4-alkyloxybenzoic acid (A1–A18) (1 mmol) in dichloromethane
(DCM) (5 mL) was added (E)-2-methoxyethyl 3-(4-hydroxyphenyl)acrylate (4b)
(1.1 mmol). Further, N,N’-dicyclohexylcarbodiimide (DCC) (1.5 mmol) was added to the
reaction mixture followed by 4-dimethylaminopyridine (DMAP) (0.05 mmol). The
resulting solution stirred for 12–16 h at room temperature. After completion of the reac-
tion mixture, the reaction mixture was filtered, the filtrate was concentrated under vac-
uum to give the crude product which was purified column chromatography to give
targeted molecules (V1–V18) as white solid.
2.1.8. General method for the synthesis of (E)-4-(3-(2-(2-methoxyethoxy)ethoxy)-3-
oxoprop-1-en-1-yl)phenyl 4-alkoxybenzoate (M1–M18)
To a stirred solution of 4-alkyloxybenzoic acid (A1–A18) (1 mmol) in dichloromethane
(DCM) (5 mL) was added (E)-2-(2-methoxyethoxy)ethyl 3-(4-hydroxyphenyl)acrylate
(4c) (1.1 mmol). Further, N,N’-dicyclohexylcarbodiimide (DCC) (1.5 mmol) was added
to the reaction mixture followed by 4-dimethylaminopyridine (DMAP) (0.05 mmol).
The resulting solution stirred for 12–16 h at room temperature. After completion of the
reaction mixture, reaction mixture was filtered, the filtrate was concentrated under vac-
uum to give the crude product which was purified column chromatography to give tar-
geted molecules (M1–M18) as white solid.
Spectral data of all synthesized compounds (P1–P18), (V1–V18), and (M1–M18) are
mentioned in Supporting Information.
2.2. Biological assay
2.2.1. In vitro antibacterial and antifungal activity
The all newly synthesized compounds (P1–P18), (V1–V18), and (M1–M18) were eval-
uated for their antibacterial activity using the Gram-positive and Gram-negative strains.
Two strains of Gram-positive bacteria (Staphylococcus aureus MTCC 96 and
Streptococcus pyogenes MTCC 442) and two strains of Gram-negative bacteria
(Escherichia coli MTCC 443 and Pseudomonas aeruginosa MTCC 1688) as well as three
fungal strains (Aspergillus clavatus MTCC 1323, Candida albicans MTCC 227, and
Aspergillus niger MTCC 282) by using the reported agar dilution method [34].
Ciprofloxacin, ampicillin, and chloramphenicol were used as a standard drug for the
antibacterial activity, and greseofulvin and nystatin were used as a standard drug for the
antifungal activity.

6
P. C. BHALODIYA ET AL.
2.2.2. In vitro antimalarial and anti-tuberculosis activity
All the synthesized compounds (P1–P18), (V1–V18), and (M1–M18) were evaluated in
in vitro antimalarial activity as per the reported method against the Plasmodium falcip-
arum strain [35] and in vitro anti-tuberculosis activity as per the reported method
against the H37RV strain [36].
3. Result and discussion
Primarily, we have prepared 4-alkoxybenzoic acid (A1–A18) from the reaction of 4-hydrox-
ybenzoic acid with 1-alkylbromide in presence of catalytic amount of KOH and KI under
refluxing ethanol for 12 h. Here, we have used various 1-alkylbromide having different long
chain from C1 to C18. Conversely, we have prepared (E)-3-(4-hydroxyphenyl)acrylic acid
(2) through the reaction of 4-hydroxybenzaldehyde (1) with malonic acid in pyridine as a
solvent and a catalytic amount of aniline at 65 ꢀC for 8h. After that, (E)-2-bromoethyl 3-(4-
hydroxyphenyl)acrylate (4a) was synthesized from the reaction of derivative (2) and 1,2-
dibromoethane (3a) in presence of triethylamine (TEA) at 65 ꢀC for 4h. Finally, (E)-4-(3-
(2-bromoethoxy)-3-oxoprop-1-en-1-yl)phenyl 4-alkoxybenzoate derivatives (P1–P18) were
synthesized from the reaction of (E)-2-bromoethyl 3-(4-hydroxyphenyl)acrylate (4a) with
derivatives (A1–A18) in the presence of N,N’-dicyclohexylcarbodiimide (DCC) and 4-dime-
thylaminopyridine (DMAP) in DCM at room temperature for 16 h. Afterward, (E)-2-
methoxyethyl 3-(4-hydroxyphenyl)acrylate (4b) was prepared from the reaction of deriva-
tives (2) and 2-methoxyethanol (3b) in the presence of triphenylphosphine (PPh3) and dii-
sopropyl azodicarboxylate (DIAD) in THF at 0 ꢀC to rt for 8 h. Likewise, (E)-2-(2-
methoxyethoxy)ethyl 3-(4-hydroxyphenyl)acrylate (4c) was synthesized by utilizing 2-(2-
methoxyethoxy)ethanol (3c) instead of 2-methoxyethanol (3) under similar reaction condi-
tions. Finally, (E)-4-(3-(2-methoxyethoxy)-3-oxoprop-1-en-1-yl)phenyl 4-alkoxybenzoate
derivatives (V1–V18) were prepared from the reaction of (E)-2-methoxyethyl 3-(4-hydroxy-
phenyl)acrylate (4b) with derivatives (A1–A18) in the presence of N,N’-dicyclohexylcarbo-
diimide (DCC) and 4-dimethylaminopyridine (DMAP) in DCM at room temperature for
12-16 h. Likewise, (E)-4-(3-(2-(2-methoxyethoxy)ethoxy)-3-oxoprop-1-en-1-yl)phenyl 4-
alkoxybenzoate derivatives (M1–M18) were synthesized by using (E)-2-(2-methoxyethox-
y)ethyl 3-(4-hydroxyphenyl)acrylate (4c) instead of (E)-2-methoxyethyl 3-(4-hydroxypheny-
l)acrylate (4b) under similar reaction conditions. All the newly synthesized derivatives
(P1–P18), (V1–V18), and (M1–M18) were purified either by column chromatography
(Tables 1 and 2).
The reaction proceeded smoothly and provided excellent yields in all cases (Tables 1 and
2). Various long carbon chain alkyl bromides reacted smoothly with this protocol to afford
the excellent yields of the products. The purity of the synthesized compounds was con-
firmed by TLC and elemental analysis. The structure of the final products was well charac-
1
terized by spectral analysis techniques like IR, H-NMR, 13C-NMR, and ESI-MS.
IR spectra displayed that two peaks between 3080 and 2930 cmꢁ1 are corresponding
to -CH Stretching of alkane and alkene, respectively. Furthermore, Peak near 1725 cmꢁ1
is corresponding to -CO starching of a,b-unsaturated ester. In addition, peak near
1215 cmꢁ1 is corresponding to -CO starching of alkyl aryl ether. Finally, peaks between
1
510 and 520 cmꢁ1 are corresponding to -C-Br group. The H-NMR spectrum showed

MOLECULAR CRYSTALS AND LIQUID CRYSTALS
7
Table 1. (E)-4-(3-(2-bromoethoxy)-3-oxoprop-1-en-1-yl)phenyl 4-alkoxybenzoate derivatives (P1–P18).
Compound code
R
Time (h)
% Yielda
M.P. (ꢀC)
P1
P2
P3
P4
P5
P6
P7
P9
P10
P12
P14
P18
CH3
12
14
16
14
15
13
12
16
16
12
14
13
78
79
82
77
85
86
83
75
76
80
78
75
121–123
109–110
103–105
101–102
91–93
84–85
81–82
73–75
68–70
58–60
82–83
C2H5
C3H7
C4H9
C5H11
C6H13
C7H15
C9H19
C10H21
C12H25
C14H29
C18H37
96–98
a¼ Isolated yields.
Table 2. Synthesis of (E)-4-(3-(2-methoxyethoxy)-3-oxoprop-1-en-1-yl)phenyl 4-alkoxybenzoate deriv-
atives (V1–V18) and (E)-4-(3-(2-(2-methoxyethoxy)ethoxy)-3-oxoprop-1-en-1-yl)phenyl 4-alkoxyben-
zoate derivatives (M1–M18).
Comp. code
R
Time (h) % Yielda M.P. (ꢀC) Comp. code
R
Time (h) % Yielda M.P. (ꢀC)
V1
V2
V3
V4
V5
V6
V7
V9
V10
V12
V14
V18
CH3
C2H5
C3H7
C4H9
C5H11
C6H13
C7H15
C9H19
C10H21
C12H25
C14H29
C18H37
14
12
16
12
16
15
16
14
14
13
12
16
83
78
82
77
84
82
79
85
78
82
84
78
77–79
75–76
66–67
69–71
60–61
39–40
42–44
44–46
49–50
58–59
64–66
82–83
M1
M2
M3
M4
M5
M6
M7
M9
M10
M12
M14
M18
CH3
C2H5
C3H7
C4H9
C5H11
C6H13
C7H15
C9H19
C10H21
C12H25
C14H29
C18H37
16
14
15
13
12
16
15
15
14
12
13
16
80
78
81
79
76
86
85
75
82
81
79
80
41–42
54–56
50–51
45–46
54–55
48–49
49–51
52–53
54–55
57–58
61–63
67–69
a¼ Isolated yields.
triplet nearer 4.5 ppm indicates a proton of the -CO–O-CH2- linkage, while triplet
1
nearer 3.6 ppm indicates a proton of the –CH2Br group. The H-NMR spectrum showed
five triplets near 4.35–4.40, 4.01–4.10, 3.75–3.82, 3.65–3.75, and 3.60–3.55 ppm indicates
protons of -OCH2 or -CH2O linkage, while singlet nearer 3.42 ppm is corresponding to
the -OCH3 group. In addition, peaks between 6.6 and 8.8 ppm were observed for
respective aromatic protons. Furthermore, doublets between 7.80–7.72 and 6.50–6.42 are
corresponding to allylic protons (-CH ¼ CH-). The 13C-NMR spectrum displayed peak
nearer 165 to 166 ppm, which indicated C ¼ O group of ester and chalcone. The LCMS
spectra of compounds (P1–P18), showed corresponding (M þ 2)þ peak % purity. While
LCMS spectra of derivatives (V1–V18) and (M1–M18), showed corresponding
(M þ 1)þ peak with % purity.
3.1. POM investigation
The liquid crystalline properties of present synthesized target derivatives (P1–P18),
(V1–V18), and (M1–M18) were primarily investigated by POM (Figs. 1 and 2). The
liquid crystalline properties of present synthesized compounds (P1–P18) were observed
on heating and cooling condition. We have noticed that, lower chain substituted

8
P. C. BHALODIYA ET AL.
Figure 1. (a) Smectic phase at 93 ꢀC for comp. P4; (b) Smectic phase at 102 ꢀC for comp. P9.
derivatives (P1–P2) does not exhibited any liquid crystalline phases on heating as well
as cooling conditions. Compounds (P3–P7) exhibited only nematic phase while com-
pound (P9–P18) showed SmC phase. Compound (P3) showed crystalline phase at 98 ꢀC
for nematic type pattern and further on heating converted to liquid at 136 ꢀC. On cool-
ing condition, it showed phase behavior reversibly at 114 ꢀC at isotropic to nematic
phase and at 78 ꢀC for nematic to solid crystalline phase, respectively. Compound (P4)
showed crystalline phase at 93 ꢀC for nematic phase and isotropic at 119 ꢀC on heating
conditions and also showed reversibly 110 ꢀC at isotropic phase to nematic phase and
88 ꢀC to smectic C to crystaliine phase on cooling conditions. Compound (P5–P7)
showed crystalline phase which transformed at 79–85 ꢀC for nematic phase and
110–114 ꢀC at isotropic phase on heating conditions and also displayed reversibly at
101–106 ꢀC at isotropic to nematic phase and at 61–69 ꢀC for nematic to crystalline
phase on cooling conditions. Similarly, Compound (P9) showed liquid crystalline phase
at 69 ꢀC which confirms the exhibition of smectic C phase and further convert in to
liquid at 102 ꢀC on heating and also showed reversibly 90 ꢀC at isotropic to smectic
phase and 55 ꢀC to smectic to crystalline phase on cooling conditions. Higher alkoxy
chain substituted compounds (P10 & P12) showed SmC phase at 80–84 ꢀC which is
further converted into isotropic state at 116–120 ꢀC on heating and also exhibited at
101–104 ꢀC for (I-SmC) and at 63–68 ꢀC for (SmC-Cr) phase on cooling condition. All
the derivatives showed threaded and schlieren type texture pattern of nematic phase
while focal conic and needle type texture pattern (Fig. 1). Compound (P14) and (P18)
showed 96 ꢀC and 106 ꢀC to smectic Phase and 130 and 134 ꢀC to isotropic phase on
heating conditions, respectively and reversibly, 76–120 ꢀC for isotropic to smectic phase
and 41–85 ꢀC at smectic to crystalline phase on cooling conditions. The mesophase tem-
perature range and phase transition curve is given in below Figs. 3–5.
Conversely, the texture pattern of crystalline and smectic phase observed in com-
pounds (V1–V18) on heating as well as cooling condition, respectively. Compound
(V1) and (V3) did not displayed any phase in heating and cooling conditions.
Compound (V2) showed crystalline phase which converted at 82 ꢀC to a smectic phase
and 103 ꢀC at isotropic phase on heating conditions and also showed reversibly 96 ꢀC at
isotropic to a smectic phase and 70 ꢀC to smectic to a crystaline phase on cooling

MOLECULAR CRYSTALS AND LIQUID CRYSTALS
9
Figure 2. (a) Smectic C phase at 93 ꢀC for comp. V4; (b) Smectic C phase at 82 ꢀC for comp. V2; (c)
Smectic C phase at 42˚C for comp.M4; (d) Smectic C phase at 51 ꢀC for comp.M2.
Figure 3. Bargraph showing the thermal stability of compounds (P1–P18) by POM.

10
P. C. BHALODIYA ET AL.
Figure 4. Phase diagram of compound (P1–P7) by POM.
Figure 5. Phase diagram of compound (P9–P18) by POM.
conditions. Compound (V4) showed a crystalline phase which converted at 62 ꢀC to a
smectic phase and 82 ꢀC at the isotropic phase on heating conditions and also showed
reversibly 77 ꢀC at the isotropic phase to smectic phase and 45 ꢀC to smectic to crysta-
line phase on cooling conditions. Compound (V5–9) showed crystalline phase which
transformed at 47–57 ꢀC to smectic phase and 71–79 ꢀC at isotropic phase on heating
conditions and also exhibited reversibly 65–72 ꢀC at isotropic to smectic phase and
37–51 ꢀC to smectic to crystaline phase on cooling conditions. Compound (V10) and
(V12) showed 62 ꢀC and 65 ꢀC to smectic phase and 80 ꢀC to isotropic phase for both

MOLECULAR CRYSTALS AND LIQUID CRYSTALS
11
Figure 6. Bargraph showing the thermal stability of compounds (V1–V18) by POM.
of them on heating conditions, respectively, and also showed 71–73 ꢀC for isotropic to
smectic phase and 52–54 ꢀC at smectic to crystalline phase on cooling conditions.
Similarly, compound (V14) showed the crystalline phase which altered at 69 ꢀC to smec-
tic phase and 79 ꢀC at isotropic phase on heating conditions and also showed reversibly
76 ꢀC at isotropic to smectic phase and 41 ꢀC to smectic to crystaline phase on cooling
conditions. Compounds (V18) showed nematic phase at 76 ꢀC which is further isotropic
at 97 ꢀC on heating conditions and showed isotropic to smectic phase at 92 ꢀC and
smectic to crystalline phase at 60 ꢀC on cooling conditions. The mesophase temperature
range and phase transition curve is given in below (Figs. 6 and 7).
The liquid crystalline phases of present synthesized derivatives (M1–M18) were pri-
marily investigated by POM and the texture images of selected compounds are depicted
in Fig. 2, respectively. It can be observed that the texture pattern of crystalline and
smectic phase in compounds (M1–M18) on heating as well as cooling condition,
respectively. Compound (M1) does not show any phase in heating and cooling condi-
tions. Compound (M2) showed crystalline phase which converted at 51 ꢀC to smectic
phase and 69 ꢀC at the isotropic phase on heating conditions and also showed reversibly
58 ꢀC at isotropic phase to smectic phase and 48 ꢀC to smectic phase to crystalline phase
on cooling conditions. Compound (M3) showed the crystalline phase which converted
at 50 ꢀC to smectic phase and 61 ꢀC at isotropic phase on heating conditions and also
showed reversibly 55 ꢀC at isotropic phase to smectic phase and 45 ꢀC to smectic to
crystalline phase on cooling conditions. Compound (M4–5) showed 42 ꢀC and 36 ꢀC to
smectic Phase and 50 ꢀC and 46 ꢀC to isotropic phase on heating conditions, respectively
and reversibly, 46 ꢀC and 42 ꢀC for isotropic to smectic phase and 39 ꢀC and 31 ꢀC for
smectic to crystalline phase on cooling conditions. Similarly, compound (M6–7) showed
crystalline phase which transformed at 48–49 ꢀC to smectic phase and 56–58 ꢀC at

12
P. C. BHALODIYA ET AL.
Figure 7. Phase diagram of compounds (V1–V18) by POM.
isotropic phase on heating conditions and also exhibited reversibly 53–55 ꢀC at isotropic
to smectic phase and 43–46 ꢀC to smectic to crystalline phase on cooling conditions.
Compounds (M9) and (M10) showed smectic phase at 50–56 ꢀC which is further iso-
tropic at 60–78 ꢀC on heating conditions and showed isotropic to smectic phase at
56–71 ꢀC and smectic to crystalline phase at 43–48 ꢀC on cooling conditions.
Compound (M12) showed crystalline phase which converted at 55 ꢀC to smectic phase
and 85 ꢀC at isotropic phase on heating conditions and also showed reversibly 74 ꢀC at
isotropic phase to smectic phase and 47 ꢀC to smectic to crystalline phase on cooling
conditions. Compound (M14) showed crystalline phase which converted at 53 ꢀC to
smectic phase and 70 ꢀC at isotropic phase on heating conditions and also showed
reversibly 65 ꢀC at isotropic phase to smectic phase and 46 ꢀC to smectic phase to crys-
talline phase on cooling conditions. Compound (M18) showed crystalline phase which
transformed at 65 ꢀC to smectic phase and 76 ꢀC at isotropic phase on heating condi-
tions and also exhibited reversibly 69 ꢀC at isotropic to smectic phase and 61 ꢀC to
smectic to crystalline phase on cooling conditions. The mesophase temperature range
and phase transition curve is given in below (Figs. 8 and 9).
3.2. DSC and TGA investigation
DSC is a valuable method for the detection of phase transitions temperature and also
correlates the results obtained by POM at initial level. The thermal behavior and stabil-
ity of few selected compounds were confirmed by using DSC and TGA measurement
shown in Figs. 10–17. In present study, DSC thermogram is traces in heating and cool-
ing condition. One can see that, two endothermic peaks are observed in heating condi-
tion for all derivatives and no any peaks traced on cooling condition. Compound P4 on
heating shows first endothermic peak at 92.78 ꢀC, which indicates the presence of Cr-
SmC mesophase and second endothermic peak observed at 170.29 ꢀC, which indicates
the presence of SmC-I phase transition. Compound P7 shows two endothermic peaks at
58.50 ꢀC and 153.74 ꢀC corresponding to Cr-SmC and SmC-I phase transition, which is
made a good agreement with transition temperature observed by POM. Further,

MOLECULAR CRYSTALS AND LIQUID CRYSTALS
13
Figure 8. Bargraph showing the thermal stability of compounds (M1–M18) by POM.
Figure 9. Phase diagram of compounds (M1–M18) by POM.
compound P14 shows two endothermic peaks at 78.19 ꢀC and 89.70 ꢀC on heating con-
dition to confirm the presence of SmC phase. For compound P18, the first endothermic
peak trace at 53.81 ꢀC which shows the presence of Cr-SmC phase and second endo-
thermic peak trace at 97.48 ꢀC which specifies the presence of SmC-I mesophase in
heating condition. It can be observed that higher alkyl chain substituted compounds
showed lower mesophase temperature range as compared to lower chain substituted
compounds; this is due to the flexibility of side alkoxy chain altered by variable alkyl
length which affects their properties. Further, all the four derivatives showed 5% to 6%
initial degradation at 60–100 ꢀC due to interference or lose of water and further

14
P. C. BHALODIYA ET AL.
Figure 10. DSC and TGA spectra of compound P4.
complete degradation occur at 140–160 ꢀC which clearly indicates the good thermal sta-
bility of present synthesized calamitic rod shaped LCs.
In the present study, the DSC thermogram is traced in heating and cooling condi-
tions. One can see that two endothermic peaks are observed in heating conditions for
all derivatives, and no peaks traced on cooling conditions. Compound V4 on heating
shows first endothermic peak at 50.11 ꢀC, which indicates the presence of Cr-SmC mes-
ophase and the second endothermic peak observed at 121.33 ꢀC, which indicates the
presence of SmC-I phase transition curve, respectively (Fig. 14). Compound V18 shows
two endothermic peaks at 52.54 ꢀC and 120.36 ꢀC corresponding to Cr-SmC and SmC-I
phase transition (Fig. 15). Compound M4 shows two endothermic peaks at 50.38 ꢀC
and 117.87 ꢀC on the heating condition to confirm the presence of SmC phase (Fig. 16).
For compound M14, the first endothermic peak trace at 50.64 ꢀC, which shows the pres-
ence of Cr-SmC phase and the second endothermic peak trace at 142.56 ꢀC, which
specifies the presence of SmC-I mesophase in heating condition (Fig. 17). It can be

MOLECULAR CRYSTALS AND LIQUID CRYSTALS
15
Figure 11. DSC and TGA spectra of compound P7.
observed that higher alkyl chain substituted compounds showed lower mesophase tem-
perature range as compared to lower chain substituted compounds; this is due to the
flexibility of side alkoxy chain altered by variable alkyl length which affects their proper-
ties. Further, all four derivatives showed 5% to 8% initial degradation at 60–100 ꢀC due
to interference or loss of water and further complete degradation occur at 160–220 ꢀC
which clearly indicates the good thermal stability of present synthesized calamitic rod-
shaped LCs.
3.3. Biology
All novel synthesized derivatives were screened twice against all microorganisms and
mentioned average of both tests.

16
P. C. BHALODIYA ET AL.
Figure 12. DSC and TGA spectra of compound P14.
3.3.1. In vitro antibacterial and antifungal activity
The biological assay of novel chalcone derivative of phenyl 4-(alkoxy)benzoate deriva-
tives displayed that the most of derivatives possessed outstanding potency against the
tested strains (Table 3). In general, most of the investigated molecules exhibited excel-
lent activity against Gram-positive bacterial strains as compared to Gram-negative bac-
terial strains. Most of synthesized derivatives (P1–P18) showed comparatively higher
potency against Gram-positive bacterial strains S. aureus as compared to S. pyogenes.
Specifically, compound P9, P12, and P18 (MIC ¼ 62.5 lg/mL) having longer alkyl
chain were found to be the most active against the S. aureus as compared to standard
drug Ampicillin (MIC ¼ 250 lg/mL). While compounds P3, P6, P10, and P14 (MIC ¼
100 lg/mL) exhibited exceptional potency against the S. aureus as compared to standard
drug Ampicillin (MIC ¼ 250 lg/mL), but 50% less potent then Ciprofloxacin (MIC ¼

MOLECULAR CRYSTALS AND LIQUID CRYSTALS
17
Figure 13. DSC and TGA spectra of compound P18.
50 lg/mL), and Chloramphenicol (MIC ¼ 50 lg/mL). Furthermore, investigated molecules
P1, P4, and P7 having good activity against S. aureus with MIC ¼ 125 lg/mL. Rest of com-
pound showed equipotent or moderate activity against S. aureus as compared to Ampicillin.
Conversely, compounds P6 and P12 (MIC ¼ 62.5 lg/mL) were found to be most active
against S. pyogenes when compared to the standard drug Ampicillin. Moreover, investigated
molecules P9, P12, and P18 displayed equipotent activity against S. pyogenes with MIC ¼
100 lg/mL as compared to standard drug Ampicillin, but 50% less active then
Ciprofloxacin (MIC ¼ 50 lg/mL) and Chloramphenicol (MIC ¼ 50 lg/mL). Rest of mole-
cules displayed moderate potency against S. pyogenes.
Further, the biological evaluation of new (E)-4-(3-(2-methoxyethoxy)-3-oxoprop-1-
en-1-yl)phenyl 4-alkoxybenzoate derivatives (V1–V18) and (E)-4-(3-(2-(2-methoxye-
thoxy)ethoxy)-3-oxoprop-1-en-1-yl)phenyl 4-alkoxybenzoate derivatives (M1–M18)
exhibited excellent activity all against the tested strains (Table 3). Generally, most of the

18
P. C. BHALODIYA ET AL.
Figure 14. DSC and TGA spectra of compound.V4.
tested derivatives displayed outstanding potency against Gram-positive bacterial strains
as compared to Gram-negative bacterial strains. Among the prepared molecules
(V1–V18) and (M1–M18) displayed outstanding potency against Gram-positive bacter-
ial strains S. aureus as compared to other investigated bacterial strains. Precisely, com-
pound V7, V10, V12, M3, M6, M9, and M18 (MIC ¼ 62.5 lg/mL) exhibited excellent
potency against the S. aureus as compared to standard drug Ampicillin (MIC ¼ 250 lg/
mL). In addition, derivatives V2, V6, M2, M4, and M10 (MIC ¼ 100 lg/mL) possess
brilliant activity against the S. aureus as compared to standard drug Ampicillin (MIC ¼
250 lg/mL), but 50% less potent then Ciprofloxacin (MIC ¼ 50 lg/mL) and
Chloramphenicol (MIC ¼ 50 lg/mL). Moreover, among the screened compounds,
derivative V5, V9, V14, and M5 consuming good activity against S. aureus with MIC ¼
125 lg/mL. Rest of the molecules displayed equipotent or moderate activity against S.
aureus as compared to Ampicillin. Conversely, molecules V6, V9, V14, M5, and M10

MOLECULAR CRYSTALS AND LIQUID CRYSTALS
19
Figure 15. DSC and TGA spectra of compound.V18.
(MIC ¼ 62.5 lg/mL) displayed outstanding activity against S. pyogenes as compared to the
standard drug Ampicillin. Furthermore, tested derivatives V2, V7, V12, M1, M12, and M18
were found to be equipotent as like Ampicillin (MIC ¼ 100 lg/mL), but 50% less active
then Ciprofloxacin (MIC ¼ 50 lg/mL) and Chloramphenicol (MIC ¼ 50 lg/mL) against S.
pyogenes. Other investigated derivatives exhibited moderate activity against S. pyogenes.
Conversely, the bio-assay results of Gram-negative bacterial strains revealed that com-
pounds P6, P10, and P18 exhibited excellent activity with MIC ¼ 62.5 lg/mL against E.
coli bacterial strain as compared to standard drug Ampicillin (MIC ¼ 100 lg/mL). In
addition, compounds P7, P9, and P10 (MIC ¼ 100 lg/mL) exhibited equipotent activity
against the E. coli as compared to standard drug ampicillin. Rest of the derivatives dis-
played moderate potency against Gram negative E. coli. However, Gram negative P. aer-
uginosa bacterial strain did not showed better sensitivity toward all investigated

20
P. C. BHALODIYA ET AL.
Figure 16. DSC and TGA spectra of compound.M4.
molecules (P1–P18). Furthermore, V6, V7, V18, M9, M10, and M18 revealed outstand-
ing potency with MIC ¼ 62.5 lg/mL against E. coli bacterial strain as compared to
standard drug Ampicillin (MIC ¼ 100 lg/mL). Furthermore, molecules V9, V10, M6,
M7, and M12 (MIC ¼ 100 lg/mL) demonstrated equipotent activity against the E. coli
as compared to standard drug ampicillin. Rest of the derivatives showed moderate
potency against Gram negative E. coli. Surprisingly, all investigated molecules (V1–V18)
and (M1–M18) were showed moderate or poor activity against Gram negative P. aerugi-
nosa bacterial strain.
Concerning the antifungal activity of all investigated molecules (P1–P18), only one
strain, i.e., C. albicans, exhibited definite sensitivity toward some of the tested com-
pounds, whereas the other two fungal strains were insensitive toward the same com-
pounds (Table 3). The molecules P2, P3, and P5 exhibited (MIC ¼ 250 lg/mL) having
shortest alkoxy chain displayed excellent activity against the C. albicans. Whereas com-
pounds P1, P6, and P9 (MIC ¼ 500 lg/mL) diplayed equipotent activity against C

MOLECULAR CRYSTALS AND LIQUID CRYSTALS
21
Figure 17. DSC and TGA spectra of compound.M14.
albicans, when compared with standard reference drug Greseofulvin (MIC ¼ 500 lg/
mL). Furthermore, derivatives (V1–V18) and (M1–M18) were also evaluated for their
anti-fungal activity and bio-assay results revealed that most of the derivatives were
active only against C. albicans, whereas the other two fungal strains were insensitive
toward the same compounds (Table 3). The compounds V1, V5, V6, M1, and M6 dis-
played excellent potency with MIC ¼ 250 lg/mL against the C. albicans. Whereas com-
pounds V2, V3, V4, V10, V14, M2, M3, M6, M9, and M14 (MIC ¼ 500 lg/mL)
demonstrated equipotent activity against C albicans as compared with standard refer-
ence drug Greseofulvin (MIC ¼ 500 lg/mL).
3.3.2. In vitro antimalarial activity
All the prepared molecules were investigated for their in vitro antimalarial activity
against Plasmodium falciparum (Pf) 3D7 chloroquine-sensitive strain. All screenings

22
P. C. BHALODIYA ET AL.
Table 3. In vitro biological activity of targeted compounds (V1–V18) and (M1–M18).
Anti-tuberculosis
activitye
Anti-malarial activityd
Antibacterial activity
MIC (mg/mL)
Antifungal activity
MIC (mg/mL)
mean IC50
(mg/mL)
Pfd
MIC
Comp. code
(mg/mL)
Eca
Paa
Sab
Spb
Cac
Anc
500
>1000
1000 >1000
500 1000
250 >1000
500
1000
500
250 >1000
500
1000 >1000
500 500
250 >1000
250
>1000
500 >1000
500 1000
>1000 >1000
500 >1000
>1000
250 >1000
500
500
Acc
H37RVe
V1
V2
V3
V4
V5
V6
V7
V9
V10
V12
V14
V18
M1
M2
M3
M4
M5
M6
M7
500
125
250
500
125
62.5
62.5
100
100
125
125
62.5
500
250
200
125
250
100
100
62.5
62.5
100
200
62.5
500
500
250
500
250
62.5
100
100
62.5
100
125
62.5
–
500
250
250
500
250
100
200
62.5
100
62.5
200
125
500
250
250
500
250
100
200
62.5
100
62.5
200
125
500
250
250
500
250
100
200
62.5
100
62.5
200
125
–
250
100
200
250
125
100
62.5
125
62.5
62.5
125
250
200
100
62.5
100
125
62.5
200
62.5
100
250
250
62.5
125
250
100
125
250
100
125
62.5
100
62.5
100
62.5
–
200
100
200
125
250
62.5
100
62.5
250
100
62.5
250
100
200
250
250
62.5
200
250
200
62.5
100
125
100
250
250
125
250
125
62.5
250
100
200
100
62.5
100
–
250
500
500
500
250
250
1000
1000
500
1000
500
0.29
0.21
0.24
0.43
0.68
0.98
1.07
0.95
1.13
1.24
1.09
1.18
0.22
0.29
0.25
0.41
0.74
1.34
1.17
0.79
1.12
1.44
1.57
1.62
0.43
0.22
0.54
0.61
0.98
1.09
1.07
0.89
1.12
0.96
1.43
1.88
–
100
250
100
62.5
100
62.5
62.5
100
50
1000
500
500
1000 >1000
62.5
25
25
500
1000
250
500
500
1000
250
500
1000
500
250
1000
500
100
250
100
100
50
62.5
100
50
1000
500
M9
500
M10
M12
M14
M18
P1
P2
P3
P4
P5
P6
P7
25
62.5
50
1000
500
500
500
1000 >1000
25
500
250
250
1000
500 >1000
1000
250
250
100
250
100
62.5
250
100
50
62.5
62.5
50
0.20
0.25
–
–
–
–
–
–
–
–
–
500
1000
500
1000 >1000
250
500
1000
500
250
1000
500 >1000
250 500
1000
P9
P10
P12
P14
P18
INHf
RIFAf
CHLf
AMPf
CIPf
NORf
GENf
NYSf
GREf
QUIf
CHLOf
1000 >1000 >1000
1000
1000 >1000
1000
–
500
1000
1000
500
500
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
50
100
25
10
0.05
–
–
–
–
–
–
–
50
100
50
10
0.5
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
50
–
25
50
250
50
10
1
–
10
0.25
–
100
500
–
100
100
–
100
100
–
–
–
–
–
0.268
0.020
–
–
–
–
–
Note: –: not tested.
aValues expressed in lg/mL, Escherichia coli MTCC 443 (Ec), Pseudomonas aeruginosa MTCC 1688 (Pa).
bValues expressed in lg/mL, Staphylococcus aureus MTCC 96 (Sa), Streptococcus pyogenes MTCC 442 (Sp).
cValues expressed in lg/mL, Candida albicans MTCC 227 (Ca), Aspergillus niger MTCC 282 (An), Aspergillus clavatus MTCC
1323 (Ac).
dValues expressed in IC50 lg/mL, Plasmodium falciparum.
eValues expressed in MIC lg/mL, H37RV strain.
fStandard drugs (INH: Isoniazid; CHL: Chloramphenicol; AMP: Ampicillin; CIP: Ciprofloxacin; NOR: Norfloxacin; GEN:
Gentamycin; NYS: Nystain; GRE: Greseofulvin; Qui: Quinine; Chlo: Chloroquine; Rif: Rifampicin).

MOLECULAR CRYSTALS AND LIQUID CRYSTALS
23
were performed in duplicate, and the mean IC50 values are displayed in Table 3. From
the investigated molecules (P1–P18), derivatives P1–P5, P9, and P12 showed good
potency against the P. falciparum strain with IC50 values between 0.22 and 0.98 lg/mL.
However, derivative P2 having shortest alkyl chain showed best potency as compared to
other synthesized molecules. Other remaining derivatives also displayed a moderated
activity as compared to standard reference drugs Quinine and Chloroquine. From the
tested derivatives (V1–V18) and (M1–M18), molecules V2, V3, M1, and M3 having
shortest alkyl chain displayed excellent potency against the P. falciparum strain with
IC50 values between 0.21 and 0.25 lg/mL as compared to standard drug drugs Quinine
(Table 3). Rest of the molecules were also shown good to moderated activity as com-
pared to standard reference drugs Quinine and Chloroquine.
3.3.3. In vitro anti-tuberculosis activity
The anti-Mycobacterium tuberculosis activity was accomplished against the H37RV strain
by the broth dilution method mentioned in experimental section. Bio-assay results
revealed that compounds P10 and P18 having longer alkyl chain exhibited excellent
activity against the H37RV strain with MIC value 50 lg/mL (Table 3). Furthermore,
derivatives P6, P12, and P14 showed good activity against the same strain with MIC
value 62.5 lg/mL. Moreover, other remaining derivatives displayed poor potency when
compared with standard drugs Isoniazid and Rifampicin. Further, compounds V14,
V18, M10, and M18 having longer alkyl chain exhibited excellent potency against the
H37RV strain with MIC value 25 lg/mL (Table 3). Moreover, molecules V10 and M14
exhibited good activity against the same strain with MIC value 50 lg/mL. Furthermore,
compounds V4, V6, V7, V12, M6, and M12 demonstrated good potency against the
H37RV strain with MIC value 62.5 lg/mL. Rest of the derivatives shown poor potency
when compared with standard drugs Isoniazid and Rifampicin.
4. Conclusion
In summary, we have successfully synthesized a newly calamitic shaped cinnamate-
ester-based homologues series (P1–P18), (V1–V18), and (M1–M18). We have found
that the present synthesized homologous series (P1–P18) showed smectic as well as
nematic phase. Furthermore, the lower member of the series exhibited nematic phase
while higher member display only SmC mesophase with good temperature range. We
have found that the present prepared homologous series (V1–V18) and (M1–M18)
showed smectic C mesophase without exhibition of the nematic phase in some hom-
logue. In addition, the lower member of the series exhibited only SmC mesophase with
good thermal stability and temperature range. The structure–property relationships of
present synthesized compounds have also been study. We have confirmed the liquid
crystalline property by DSC, POM, and the stability of the compounds were examined
by TGA analysis. Furthermore, most of cinnamate-based liquid crystalline materials pos-
sessed exceptional anti-microbial and anti-malarial activity. In addition, all the com-
pounds exhibited excellent potency against S. aureus bacterial strain while some
molecules also displayed brilliant anti-fungal potency against C. albicans. Moreover,
among the synthesized compounds, derivative P2 having shortest alkyl chain showed

24
P. C. BHALODIYA ET AL.
highly potent anti-malarial activity. Some derivatives also exhibited good anti-tubercu-
losis and anti-fungal activity.
Acknowledgments
Authors acknowledge thanks to Department of Chemistry, Shri M.M Patel Institute of Sciences
and Research, Kadi Sarva Vishwavidyalaya, Gandhinagar.
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