Mesomorphism dependence on ortho-substituted lateral groups in isomeric and nonisomeric homologous series

Article abstract of DOI:10.1080/15421406.2015.1068973

A novel monomeric homologous series of α,β-ethylene derivatives was synthesized and studied with a view to understanding and establishing the relation between molecular structure and liquid crystal properties. The series consists of 12 novel compounds. The methoxy to propyloxy derivatives are not liquid crystals, the butyloxy homologue is monotropic nematic, the pentyloxy homologue is monotropic smectic and enantiotropic nematic, and the rest of the homologues (C₆-C₁₆) are enantiotropically smectic in addition to nematic. Transition temperatures and texture were determined by an optical polarizing microscope equipped with a heating stage, and show an odd-even effect for nematic-isotropic and smectic-nematic transition curves. Analytical and spectral data confirm the molecular structures. The average smectic and nematic thermal stabilities are 84.9°C and 94.15°C, respectively. The liquid crystal properties of present series are compared with the structurally similar known series.

Full text of DOI:10.1080/15421406.2015.1068973

Molecular Crystals and Liquid Crystals
ISSN: 1542-1406 (Print) 1563-5287 (Online) Journal homepage: http://www.tandfonline.com/loi/gmcl20
Mesomorphism dependence on ortho-substituted
lateral groups in isomeric and nonisomeric
homologous series
M. D. Khunt, V. C. Kotadiya & U. C. Bhoya
To cite this article: M. D. Khunt, V. C. Kotadiya & U. C. Bhoya (2016) Mesomorphism
dependence on ortho-substituted lateral groups in isomeric and nonisomeric
homologous series, Molecular Crystals and Liquid Crystals, 625:1, 20-29, DOI:
10.1080/15421406.2015.1068973
To link to this article: http://dx.doi.org/10.1080/15421406.2015.1068973
Published online: 19 Feb 2016.
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Date: 24 February 2016, At: 03:39

MOL. CRYST. LIQ. CRYST.
, VOL. , –

http://dx.doi.org/./..
Mesomorphism dependence on ortho-substituted lateral
groups in isomeric and nonisomeric homologous series
M. D. Khunt, V. C. Kotadiya, and U. C. Bhoya
Department of Chemistry, Saurashtra University, Rajkot, Gujarat, India
ABSTRACT
KEYWORDS
A novel monomeric homologous series of α,β-ethylene derivatives was
synthesized and studied with a view to understanding and establish-
ing the relation between molecular structure and liquid crystal prop-
erties. The series consists of 12 novel compounds. The methoxy to
propyloxy derivatives are not liquid crystals, the butyloxy homologue
is monotropic nematic, the pentyloxy homologue is monotropic smec-
tic and enantiotropic nematic, and the rest of the homologues (C –C )
Liquid crystal; mesomorphic;
monotropy; nematic; smectic
6
16
are enantiotropically smectic in addition to nematic. Transition tem-
peratures and texture were determined by an optical polarizing micro-
scope equipped with a heating stage, and show an odd–even effect
for nematic–isotropic and smectic–nematic transition curves. Analytical
and spectral data confirm the molecular structures. The average smectic
and nematic thermal stabilities are 84.9°C and 94.15°C, respectively. The
liquid crystal properties of present series are compared with the struc-
turally similar known series.
Introduction
A liquid crystalline state (LC) of a substance is known since 1888 [1], has proved its util-
ity in many of science and technology [2–5]. A critical survey of literature about the syn-
thesis and study of the LC state, it is concluded that the synthesis of novel LC substances is
an interesting and important field from research point of view. Synthesis of novel LC sub-
stances [6–10] can be useful to the researchers in other fields in addition to chemistry. Thus,
the present investigation is planned with a view to understanding the effects of molecular
structure on liquid crystal properties [11–15] by varying terminal group or groups, central
bridge or bridges, or number of phenyl ring or rings, changing the position of the functional
group or changing polarity of the functional group at lateral or/and terminal position, etc.
The present study is aimed to construct a nonlinear molecule of three phenyl rings bridged
through -COO- and -CO-CH=CH- group and -OC H
, left terminal as well as ortho sub-
stituted –Cl group. Thus, effect of molecular rigidity/flexibility related to molecular struc-
ture can be correlated with liquid crystal properties of thermotropic LC novel substances
n
2n+1
[16–18].
CONTACT U. C. Bhoya
India.
drucbhoya@gmail.com
Department of Chemistry, Saurashtra University, Rajkot , Gujarat,
Color versions of one or more of the figures in the article can be found online at www.tandfonline.com/gmcl.
©
 Taylor & Francis Group, LLC

MOL. CRYST. LIQ. CRYST.
21
Scheme . Synthetic route to the novel series.
Experimental
Synthesis
n-Alkoxy benzoic acids were prepared from 4-hydroxy benzoic acid, by suitable
alkylating agents by modified method of Dave and Vora [19]. α-4-Hydroxy benzoyl β-
ꢀ
2
-chloro phenyl ethylene was prepared by usual established method [20]. 4-n-Alkoxy
ꢀ
benzoic acids and α-4-hydroxy benzoyl-β-2 -chloro phenyl ethylene were condensed in
,3-dicyclohexylcarbodiimide (DCC), 4-dimethylaminopyridine (DMAP) and CH Cl [21].
1
2
2
Synthetic route to usual series is shown in scheme 1. Final products were individually
decomposed, filtered, washed, dried and purified till the constant transition temperatures
obtained.
The chemicals 4-hydroxy benzoic acid, 4-hydroxy acetophenone, 2-chloro benzaldehyde,
alkyl bromide (R-Br), methanol, KOH, DCC, 4-dimethylaminopyridine, hydrochloric acid,
dichloromethane, ethanol etc. were used as received except solvents, which were dried, puri-
fied and distilled prior to use.
Characterization
Some selected members of a series were characterized by elemental analysis (Table 1), IR
1
spectra, H NMR spectra and mass spectra. Transition temperatures and textures of the

2
2
M. D. KHUNT ET AL.
Table . Elemental analysis for () ethyloxy, () propyloxy, () dodecyloxy derivatives.
Elements %Found
H
Elements %Calculated
Molecular
formula
S. No.
C
O
C
H
N



C H ClO
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.




C H ClO
 
C H ClO-




nematic and smectic phase were determined by an optical polarizing microscope equipped
with a heating stage. Microanalysis was performed on Perkin Elmer PE 2400 CHN Ana-
lyzer (Table 1). The structures of the materials were elucidated by infrared (IR) spectroscopy
1
(
SHIMATZU FTIR-8400 Spectrophotometer), proton nuclear magnetic resonance ( H NMR)
spectrometry (BRUKER Advance-III (400 MHz) Spectrometer using CDCl as a solvent) and
3
Mass spectrometry (Shimadzu GC-MS Model No.QP-2010,). The analyses of the structures
of the products and intermediates by spectroscopic methods were found to be consistent with
the predicted structures.
Analytical data
Elemental analysis (Table 1)
Spectral data
H NMR in ppm for tetradecyloxy derivative
0
.77–0.79(t,3H,-CH of –OC H group), 1.51–1.36 (m,22H,(-CH -) ), 1.68–1.72(t,2H,-
3
14 29
2
11
CH -CH -O-), 3.89–3.92 (t,2H,-CH -O-), 6.84–6.88 (d,2H, ortho to –OC H group in
2
2
2
14 29
phenyl ring), 7.15–7.31 (s,s,s, dd 5H, ortho, pera & meta to –CO-CH=CH- & ortho to
Ph-COO-),7.36–7.40(d, 1H,-CO-CH-CH-), 7.63–7.64 (d, 1H, in phenyl ring ortho to –
Cl group),7.98–8.04(m,4H,ortho to–COO- & -CO-CH-CH- group in phenyl ring), 8.07–
8
.11(1H, d, -CO-CH-CH-)The NMR data are consistent with the molecular structure.
H NMR in ppm for hexadecyloxy derivative
0
.78–0.81 (t,3H,-CH of –OC H group),1.17–1.39 (m,26H,(-CH -) ), 1.72–1.75 (q, 2H,-
3
16 33
2
13
CH -CH -O-), 3.94–3.97 (t,2H,-CH -O-), 6.86–6.90 (d,2H, ortho to -OC H group in
2
2
2
14 29
phenyl ring), 7.17–7.37 (s,s,s, dd, 5H, ortho, pera & meta to -CO-CH=CH- & ortho to
Ph-COO-),7.37–7.44(d, 1H,-CO-CH-CH-), 7.67–7.69 (d, 1H, in phenyl ring ortho to –
Cl group),7.98–8.07(m,4H,ortho to–COO- & -CO-CH-CH- group in phenyl ring), 8.10–
8
.14(1H, d, -CO-CH-CH-). The NMR data are consistent with the molecular structure.
-
IR in cm for pentyloxy derivative
3
074 (=C-H Str. of Phenyl nucleus), 2918 & 2848 (CH sym. & asym. stra.), 1732 (Aromatic
2
C=O Str.), 1602 (aromatic C=C str.), 1506 (C–C aromatic str.), 1413 (C–H bend alkanes),
1
325 (aromatic & aliphatic C-O str.), 1168 (Ar-O str.), 850 (C-H oop. phenyl ring), 759 (C-H
oop.bending of phenyl ring). The IR data are consistent with the molecular structure.
-
IR in cm for heptyloxy derivative
3
070 (=C-H Str. of Phenyl nucleus), 2914 & 2848 (CH sym. & asym. stra.), 1730 (Aromatic
2
C=O Str.), 1602 (aromatic C=C str.), 1508 (C-C aromatic str.), 1415 (C-H bend alkanes),

MOL. CRYST. LIQ. CRYST.
23
1
313 (aromatic& aliphatic C–O str.), 1165 (Ar–O str.), 846 (C–H oop. phenyl ring), 758 (C–H
oop.bending of phenyl ring). The IR data are consistent with the molecular structure.
Mass spectra of butyloxy derivative
+
m/z (rel.int%): 434 (M) , 241,193, 136, 121
Mass spectra of octyloxy derivative
+
m/z (rel.int%): 491(M) ,377, 241,136,121,113
Results and discussion
Novel α, β ethylene derivatives of ester homologous series of liquid crystal behaviors consists
of twelve homologues. C to C members of a series are not liquid crystals and the rest of
1
3
the homologues are liquid crystals in either monotropic or enantiotropic condition. C mem-
4
ber is monotropic nematic, C member is monotropic smectic and enantiotropically nematic,
5
as well as the, rest of the homologues (C to C ) are enantiotropically, smectic in addition
6
16
to nematic. α-4-Hydroxy benzoyl β-2’-chloro phenyl ethylene (151–153°C) is a nonliquid
crystal component, however, on linking it with dimeric 4-n-alkoxy benzoic acids through
their acid chlorides yielded nine homologues with liquid crystal behaviors out of twelve in
either monotropic or enantiotropic manner. Transition temperatures (Table 2) as determined
by an optical polarizing microscopy equipped with a heating stage (POM) are plotted against
the number of carbon atoms present in n-alkyl chain (R= C H
) bonded to first phenyl
n
2n+1
ring through oxygen atom. Transition curves (Cr-I or Cr-M, Sm-N, N-I or I-N etc.) are
obtained on linking like or related points, showing phase behaviors of series in a phase dia-
gram (Fig. 1). The Cr-I or Cr-Mesomorphic transition curve adopt a zigzag path of rising and
falling tendency as series is ascended. Sm-N (or vice versa) transition curve follows serpentine
shaped path with exhibition of odd–even effect and deviating trend of propagation as series
is ascended. Similarly N-I (or vice versa) transition curve follows parallel path to Sm-N curve
in deviating manner with exhibition of odd–even effect. The curves for odd and even mem-
bers (Sm-N and N-I) merged into each other at the decyloxy (C ) derivative of a novel series
10
and then from and beyond the both curves (Sm-N and N-I) are individually follow the paths
as a single curve. Alternation of transition temperatures created the exhibition of odd–even
effects in Sm-N and N-I transition curve. Transition curves for odd members occupied lower
position than the even members of a series in case of Sm-N and N-I, both curves. Thermal
Table . Transition temperatures in °C of series-.
Transition temperature in °C
Compound no.
R= n-alkyl group
Sm
Nm
Isotropic

Methyl
Ethyl
Propyl
Butyl
Pentyl
Hexyl
Heptyl
Octyl
—
—
—
—
—
—
.
.
.
.
.
.
.
.
.
.











—
(.)
.
.
.
.
.
.
.
.
(.)
.
.
.
.
.
.
.
Decyl



Dodecyl
Tetradecyl
Hexadecyloxy
.
.
Sm- Smectic: Nm- Nematic, ( ) indicate Monotropy.

24
M. D. KHUNT ET AL.
Figure . Phase behavior of series.
stability for smectic and nematic are 84.9°C and 94.15°C, respectively. The mesophase length
for smectic and nematic ranges from 1.9°C to 27.7°C and 2.8°C to 22.4°C, respectively. Cr–Sm
transition temperatures and Sm–N transition and N–I temperatures (except C homologue)
16
of mesomorphic homologue (C to C ) are below hundred degree centigrade. Thus, present
4
14
novel homologous series is partly smectogenic and partly nematogenic with middle ordered
melting type. The liquid crystal properties are varied from homologue to homologue with
changing molecular length and polarizability as well as with the changing permanent dipole
moment across the long molecular axis and related cohesive intermolecular forces.
The lack of liquid crystal properties by C to C homologues is attributed to their high
1
3
crystallizing tendency arising from their inability to withstand the exposed thermal vibrations
from external source, due to unfavorable and unsuitable magnitudes of anisotropic forces of
intermolecular end to end and lateral attractions; as a consequence of resultant molecular
rigidity and/or flexibility, induced by low dipole–dipole interactions and dispersion forces
occurring through the interactions between instantaneous dipole produced by the sponta-
neous oscillations of the electron clouds of molecules, leading and inducing high crystallizing
tendency in a substance. Thus, liquid crystal mesophase formation is inhibits and a solid crys-
talline substances directly possess into isotropic liquid without passing through an intermedi-
ate state of existence between crystalline state and isotropic liquid state. Hence, the molecules
of C to C homologues whose crystal lattices are abruptly breaking and then sharply trans-
1
3
form into isotropic liquid under the influence of exposed thermal vibrations. Exhibition of
liquid crystal state either smectic or nematic are attributed to the disalignment of molecules
at an angle ninety or less than ninety degree on a floating surface depending upon suit-
able magnitudes of end to end or/and lateral intermolecular anisotropic forces of attractions.
Molecules of homologues C to C possess lamellar packing of molecules with layered struc-
5
16
ture and then, on heating the same the intermolecular attractive forces are loosened and lay-
ers of molecules slide upon each other. Thus, sliding layered arrangement of molecules from
focal conic fan shaped appearance under POM of the type smectic A or C enantiotropically
(
C to C ) or monotropically (C ) in reversible and irreversible manner respectively. All the
6
16
5
smectogenic homologues C to C reversibly and C homologue irreversibly exhibited
5
16
4
nematogenic mesophase formation. i.e. molecules of C to C homologues above Sm-N
5
16

MOL. CRYST. LIQ. CRYST.
25
transition temperature adopt statistically parallel orientational order of molecules in float-
ing condition, depending upon magnitudes of end to end attractions under thermal treatment
with appearance of threaded or Schlieren texture of nematic phase under POM. The C homo-
4
logue shows nematic mesophase formation below isotropic temperature in monotropic con-
dition. The n-alkoxy benzoic acids are dimeric but, their dimerization disappears on esterifi-
cation process by breaking of hydrogen bonding into two molecules. Therefore, the transition
temperatures of final ester homologues are generally lower than the corresponding n-alkoxy
benzoic acids. All the members of a series either mesomorphic or nonmesomorphic from and
beyond isotropic temperature shows high order of molecular disorder or high entropy (ꢀS =
ꢀH/T) in which the molecules of a targeted substance are randomly oriented in all possible
directions with irregular molecular arrangement. However, on cooling the same, the enan-
tiotropic homologues exhibit mesophase formation from and below isotropic temperature in
reversible manner and monotropic homologues (C and C ) exhibit smectic and/or nematic
4
5
mesophase below isotropic temperature in irreversible manner. Nonmesomorphic homo-
logues undergo crystallization below isotropic temperature if proper rate of cooling is main-
tained. The exhibition of odd–even effect by transition curves in a phase diagram is attributed
to the alternations of transition temperatures of homologues up to decyloxy (C ) homologue.
10
But, alternations diminishes as series is ascended from and beyond C homologue for longer
10
n-alkyl chains of left n-alkoxy terminal end group, because longer n-alkyl chain may coil or
bend or flex or couple to lie with major axis of the core structure of molecules. Thus, uncer-
tainty in the status of longer n-alkyl chain causes deviation in transition temperature (C )
16
and/or transition curves which follow as single transition curve without showing odd–even
effect. Odd–even effect observed in initial homologues (C , C , C and C , C ) is attributed
4
6
8
5
7
to sequentially added methylene unit or units, with probable excepted status of n-alkyl chain.
However, deviating effect in transition curves and temperatures may be attributed to the alter-
nating tendency of intermolecular anisotropic forces of attractions due to laterally substituted
polarizable –Cl group which may decrease intermolecular attractions due to increased molec-
ular width or increase the intermolecular attractions due to molecular polarizability by –Cl
group. Thus, two opposing forces operated at a time for the same reason, i.e. broadening of
molecular width by laterally substituted –Cl group which alternates the tendency of the fac-
tors inducing mesomorphism, after decyloxy (C ) homologue. The change in mesomorphic
10
properties and the degree of mesomorphism from homologue to homologue in present (or
any) homologous series is due to the progressive added methylene unit or units to the n-
alkyl chain bonded to phenyl ring through oxygen atom which varies molecular flexibility and
overall combined effect of molecular rigidity and flexibility to causes suitable magnitudes of
anisotropic forces of intermolecular attractions to induce mesophase formation. The selected
mesomorphic properties of present series are compared with the structurally similar other
known series-X [22] and Y [23] shown below in Fig. 2.
Presently investigated novel homologous series-1 and a structurally similar homol-
ogous series-X are identical with respect to three phenyl ring, i.e. aromaticity, cen-
tral bridges –COO–, and –CO–CH=CH– linking phenyl rings and left n-alkoxy
(
–OR) terminal end group which varies from homologue to homologue in same
series but remains unaltered for the same homologue from series to series under
comparison. Moreover homologous series 1 and X are isomeric and identical with
respect to functional group –Cl; but, chloro group of same group polarity occu-
pied at different positions (viz. ortho or para to –CO–CH=CH–). Thus, only the
positional difference of chloro group which causes difference in molecular polarity,
polarizability, permanent dipole moment across the long molecular axis, dipole–dipole

26
M. D. KHUNT ET AL.
Figure . Structurally similar homologous series.
interactions, dispersion forces, molecular rigidity and/or flexibility, etc. can cause alteration
for the same homologue from series to series in inducing mesomorphism and the degree of
mesomorphism. Homologous series-1 and Y are equally identical with respect to each other as
discussed earlier, except the position and group polarity of functional group on third phenyl
ring. –Cl and –NO functional groups occupy identically their substitution position (ortho
2
to –CO–CH=CH–) and induced molecular polarizability and steric hindrance in equiva-
lent manner but their extent of molecular rigidity–flexibility may differ for the same homo-
logue from series to series. Thus, homologous series 1, X and Y though structurally similar in
appearance, but their liquid crystal properties behaviors and the degree of liquid crystallinity
may differ for the same homologue from series to series depending upon even a very small
or negligible differing features of a molecular structure as a consequence of a little difference
of molecular rigidity and/or flexibility. Following Table 3 represent some LC properties, viz.
average thermal stability, commencement of LC state, mesophase length range exhibition of
odd–even effect, etc. in comparative manner, which indicate the effect of molecular structure
on liquid crystal properties and their magnitudes.
Table 3 indicates that,
r
A homologous series of present investigation-1 and a homologous series-Y chosen for
comparison are smectogenic in addition to nematogenic in behavior.
r
Homologous series-X, chosen for comparison and isomeric with series-1 is only nemato-
genic without exhibition of any smectogenic character.
r
Thermal stability of nematic mesophase progressively increases from series-1 to series-Y.
r
Smectic thermal stability of series-1 is lower than a series-Y.
r
Smectic mesophase formation commences later (C ) than a series-Y which commences
5
from third (C ) homologue of series-Y.
3
Table . Average thermal stability in °C.
Series:→
[]
[X]
[Y]
Smectic – Isotropic or Smectic - Nematic
Commencement of smectic phase
. [C -C ]
—
—
. [C -C ]




C
C
Nematic –isotropic
Commencement of nematic phase
. [C -C ]
. [C -C ]
. [C -C ]






C
C
C
Total mesophase length in °C (Sm + Nm )
. to .
 to 
 to 

MOL. CRYST. LIQ. CRYST.
27
r
r
r
r
Nematic mesophase formation commences from C , C , and C homologues for series-1,
4
5
3
series-X and series-Y, respectively.
Total mesophase length range is the highest (2.8 to 50.1) of present series-1 and the lowest
for an isomeric series-X (14 to 25) and an intermittent value (16 to 49) of series-Y.
Odd–even effects are observed for all the transition curves of series-1, X, and Y under
comparative study.
Odd membered transition curves in respective phase diagrams occupy their lower posi-
tion than the corresponding transition curves of even membered homologues for the
series under comparison.
Thus, mesomorphic properties and their degrees of mesomorphism for the same homo-
logue vary from series to series, depending upon changing part of their respective molecule
or changing position (o, m, p) of same substituent group.
The lack of smectic property by the molecules of series-X is attributed to the absence of
lamellar packing of molecules in their crystal lattices. However, the molecules of series-1 and
Y being laterally substituted by –Cl or –NO polar groups, broadens respective molecules
2
and intermolecular closeness as compared to series-X. Thus, the molecular polarizability fac-
tor activated and operates lamellar packing of molecules which builds two or three dimen-
sional network of molecules to cause sliding layered molecular arrangement under the influ-
ence of exposed thermal vibrations in case of series-Y and series-1, but the same polariz-
ability factor fails to build up sliding layered molecular arrangement under identical condi-
tion for series-X due to absence of lateral substitution. Moreover early or late commence-
ment of smectic phase depends upon the extent of noncoplanarity of molecules. The –Cl
group and –NO group of series-1 and Y though situated on identical lateral position, but,
2
their group polarities and atomic make up are different the molecules of series-X are linear
lath like. Therefore, the extent of molecular noncoplanarity vary from series to series and
smectic mesophase commences earliest (from C ) of series Y, from C for present series-
3
5
1
and it does not commence till the last homologue for series-X. Smectic and nematic ther-
mal stability of series-Y are greater than the present series-1 and even a nematic thermal
stability of series-X is though greater than a series-1 but it is lower than series-Y. The suit-
able magnitudes of anisotropic forces of intermolecular end to end attractions for the same
homologue from series to series vary depending upon intermolecular closeness and ther-
mal resistivity associated with molecular rigidity and flexibility in terms of enthalpy (ꢀH)
or internal energy which, vary from homologue to homologue in a same series and series
to series for same homologue. The highest total mesophase length range (2.8 to 50.1) indi-
cated for a present series is attributed to the degree of thermal resistivity against exposed
thermal vibrations possessed by the molecules of respective series-1, X and Y after acquir-
ing suitable magnitudes of anisotropic forces of intermolecular attractions and favorable
enthalpy values, to cause mesomorphism. Exhibition of odd–even effect by initial members
of the series are due to the expected status of the n-alkyl chain which alternates the transi-
tion temperatures as per expected manner, but alternation diminishes as series is ascended
due to uncertainty in the status of flexible n-alkyl chain arising for different uncontrollable
reasons.
Conclusions
r
Presently investigated series is partly smectogenic and partly nematogenic whose,
thermal stability and transition temperatures of mesomorphic homologues are below
1
00°C (except C homologue).
16

28
M. D. KHUNT ET AL.
r
r
Laterally substituted homologous series increases molecular polarizability and reduces
transition temperatures.
The group efficiency order derived on the basis of (i) thermal stability, (ii) early com-
mencement of mesophase, and (iii) total mesophase length range (Sm + N) or for smec-
tic and/or nematic are as under.
(
i) Smectic: ortho - NO > ortho –Cl > para –Cl
2
Nematic: ortho - NO > para –Cl > ortho –Cl
2
(
ii) Smectic: ortho - NO > ortho –Cl > para –Cl
2
Nematic: ortho - NO > ortho –Cl > para –Cl
2
(
iii) Smectic+ Nematic : ortho –Cl > ortho - NO > para–Cl
2
r
Molecular rigidity and flexibility of suitable magnitudes are useful to induce mesomor-
phism.
r
Phenomena of mesomorphism and the degree of mesomorphism are very sensitive and
susceptible to molecular structure.
r
Present investigation may be useful (i) to construct LC devices workable below 100°C or
below 40°C to 46°C by binary mixture study with C and C homologues (ii) to study
7
10
biological activity of the novel compounds which may prove their ability as anticancer,
anti-malaria, anti-inflammatory, etc. [24–28].
Acknowledgment
Authors acknowledge thanks to the Department of Chemistry (DST-FIST Funded & UGC-SAP Spon-
sored) Saurashtra University, Rajkot, for research work. Authors are also thankful to Dr. A.V. Doshi,
Ex. Principal M.V.M. Science and Home Science College Rajkot, for his valuable co-operation during
present investigation as and when needed. Also thanks are due to the National Facility for Drug Dis-
covery through New Chemical Entities (NCEs), for analysis of samples.
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