Synthesis and biological screening of 2′-aryl/benzyl-2-aryl-4-methyl-4′,5-bithiazolyls as possible anti-tubercular and antimicrobial agents

Article abstract of DOI:10.1016/j.ejmech.2015.03.016

A series of 2′-aryl/benzyl-2-aryl-4-methyl-4′,5-bithiazolyl derivatives, 25-64 were synthesized and evaluated for inhibitory activity against Mycobacterium smegmatis MC² 155 strain and antimicrobial activities against four pathogenic bacteria Bacillus subtilis, Staphylococcus aureus, Escherichia coli and Proteus vulgaris. Among them, compounds 40, 49, 50, and 54 exhibited moderate to good inhibition on the growth of the bacteria Mycobacterium smegmatis at the concentration of 30 μM. Compounds 26, 40, 44, 54 and 56 exhibited moderate to good antibacterial activity. Compound 5-(2′-(4-fluorobenzyl)thiazol-4′-yl)-2-(4-fluorophenyl)-4-methyl-thiazole (54) exhibited both antitubercular as well as antimicrobial activity against all tested strains.

Full text of DOI:10.1016/j.ejmech.2015.03.016

Accepted Manuscript
Synthesis and biological screening of 2′-aryl/benzyl-2-aryl-4-methyl-4′,5-bithiazolyls
as possible anti-tubercular and antimicrobial agents
Yogita K. Abhale, Amit V. Sasane, Abhijit P. Chavan, Keshav K. Deshmukh, Sudha
Sravanti Kotapalli, Ramesh Ummanni, Sadikali F. Sayyad, Pravin C. Mhaske
PII:
S0223-5234(15)00183-X
10.1016/j.ejmech.2015.03.016
EJMECH 7761
DOI:
Reference:
To appear in: European Journal of Medicinal Chemistry
Received Date: 10 January 2015
Revised Date: 5 March 2015
Accepted Date: 6 March 2015
Please cite this article as: Y.K. Abhale, A.V. Sasane, A.P. Chavan, K.K. Deshmukh, S.S. Kotapalli, R.
Ummanni, S.F. Sayyad, P.C. Mhaske, Synthesis and biological screening of 2′-aryl/benzyl-2-aryl-4-
methyl-4′,5-bithiazolyls as possible anti-tubercular and antimicrobial agents, European Journal of
Medicinal Chemistry (2015), doi: 10.1016/j.ejmech.2015.03.016.
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ACCEPTED MANUSCRIPT
Synthesis and biological screening of 2'-aryl/benzyl-2-aryl-4-methyl-4',5-
bithiazolyls as possible anti-tubercular and antimicrobial agents
Yogita K. Abhale, Amit V. Sasane, Abhijit P. Chavan, Keshav K. Deshmukh, Sudha Sravanti Kotapalli,
Ramesh Ummanni, Sadikali F. Sayyad and Pravin C. Mhaske*
CH3
CH3
CH3
S
N
Br
2
, DCM
N
N
EtOH
Br
+
H N
R1
2
S
rt, 24 h
S
S
S
Reflux
R
R
N
R
O
O
R1
7-10
11-14
15-24
25-64

ACCEPTED MANUSCRIPT
Synthesis and biological screening of 2'-aryl/benzyl-2-aryl-4-methyl-4',5-bithiazolyls as
possible anti-tubercular and antimicrobial agents
a
b
b
a
c
Yogita K. Abhale, Amit V. Sasane, Abhijit P. Chavan, Keshav K. Deshmukh, Sudha Sravanti Kotapalli, Ramesh
c
d
b
Ummanni, Sadikali F. Sayyad and Pravin C. Mhaske *
a
Post-Graduate Department of Chemistry and Research Centre, S. N. Arts, D. J. M. Commerce and B. N. S. Science
College, College Road, Sangamner, District Ahmednagar, India 422 605, (Affiliated to University of Pune)
b
Post Graduate Department of Chemistry, S. P. Mandali’s Sir Parashurambhau College, Tilak Road, Pune, India 411
0
30, (Affiliated to University of Pune).
Fax: 91-020-24332479; Tel: 91-020-24331978; E-mail: mhaskepc18@gmail.com
c
Center for Chemical biology, CSIR-Indian Institute of Chemical Technology, Hyderabad,500 007, India.
Amrutvahini College of Pharmacy, Amrutnagar, P. O. Sangamner (S.K.), Tal. Sangamner, Dist. Ahmednagar,
d
Maharashtra, India 422 608, (Affiliated to University of Pune).
Keywords: Bithiazoles, Mycobacterium smegmatis, Antibacterial activity
Abstract
A series of 2'-aryl/benzyl-2-aryl-4-methyl-4',5-bithiazolyl derivatives, 25-64 were synthesized and
2
evaluated for inhibitory activity against Mycobacterium smegmatis MC 155 strain and antimicrobial
activities against four pathogenic bacteria Bacillus subtilis, Staphylococcus aureus, Escherichia coli and
Proteus vulgaris. Among them, compounds 40, 49, 50, and 54 exhibited moderate to good inhibition on the
growth of the bacteria Mycobacterium smegmatis at the concentration of 30 µM. Compounds 26, 40, 44, 54
and 56 exhibited moderate to good antibacterial activity. Compound 5-(2′-(4-fluorobenzyl)thiazol-4′-yl)-2-
(4-fluorophenyl)-4-methyl-thiazole (54) exhibited both antitubercular as well as antimicrobial activity
against all tested strains.
1

ACCEPTED MANUSCRIPT
1
. Introduction
Tuberculosis is a contagious disease with comparatively high mortality worldwide [1-3]. The last
major clinical advance in tuberculosis chemotherapy was the introduction of Rifampicin in 1968 [4]. With
the emergence of multidrug resistant tuberculosis (MDR-TB), extensively drug-resistant tuberculosis
(XDR-TB) worldwide, WHO has declared TB as a global emergency [5-7].
Thiazole and its derivatives are important pharmacophore and coupled with other heterocyclic rings
have furnished new biologically active compounds [8-10]. Thiazole containing compounds have exhibited a
broad range of biological activities such as anti-tumor [11,12], anti-cancer [13], anti-inflammatory [13-17],
antibacterial and antifungal [18-22], anti-tubercular [23-25] and antiviral [26] activity. Bithiazoles and
directly linked polyazoles containing compounds are the backbone of bioactive natural products and
thiopeptide antibiotics (Figure 1) [27,28]. Bithiazoles (cystothiazoles A-F), isolated from the
myxobacterium culture broth of Cystobacter fuscus, has demonstrated potent antifungal activity against the
phytopathogenic fungus Phytopathora capsici [29,30]. Large numbers of bisazole have been synthesized by
several groups and screened for their biological activities [31-38]. 2'-Alkyl/aryl-2-aryl-4-methyl-4',5-
bithiazolyls showed antiinflammatory activity [39] and thiazole linked with other azoles have exhibited
anti-tubercular activity [23,24]. In view of these observations, we report herein the synthesis of 2'-
aryl/benzyl-2-aryl-4-methyl-4',5-bithiazolyls via Hantzsch cyclocondensation and their antimycobacterial
activity.
<
Figure 1>
2
. Chemistry
The synthesis of 2'-aryl/benzyl-2-aryl-4-methyl-4',5-bithiazolyls, 25-64 was achieved according to
Scheme 1. Acetyl acetone 1 on reaction with p-toluene sulphonic acid and NBS in DCM:diethyl ether (1:1)
gave 3-bromopentane-2,4-dione, 2. Further, compound 2 on cyclocondensation with aryl thioamide 3-6 in
dry ethanol gave 1-(4-methyl-2-arylthiazol-5-yl)ethanone, 7-10 [40-41]. Compounds 7-10 on bromination
with bromine and p-toluene sulphonic acid as catalyst in DCM at room temperature resulted in the
formation of 2-bromo-1-(4-methyl-2-arylthiazol-5-yl)ethanone 11-14 which on further cyclocondensation
with aryl/benzyl thioamide, 15-24 furnished target compounds, 25-64.
<Scheme 1>
The structure of the title compounds 25-64 was confirmed by elemental analysis, IR, NMR and MS.
2

ACCEPTED MANUSCRIPT
As a representative analysis of compound 40, the IR (KBr) spectrum showed C=C/C=N absorption bands at
-1
1
1
629-1475 cm . The H NMR spectrum of compound 40 displayed two singlets at δ 2.85 (CH ) and δ 7.38
3
(thiazole CH). A triplet, J = 8.4Hz, at δ 7.15 and a doublet of doublet, J = 8.4 and 3.0 Hz, 2H at δ 7.96
were attributed to protons of fluoro substituted phenyl ring, while doublets, J = 8.6 Hz, at δ 7.42 and δ 8.04
1
3
corresponds to protons of chloro substituted phenyl ring. The C NMR spectrum of compound 40 revealed
the methyl carbon signal at δ 16.3, while the aromatic carbons showed typical fluoro-coupling [C -F, δ
65.5, 163.0 ( J = 250 Hz), C -F δ 116.4, 116.1 ( J = 22 Hz), C -F δ 128.7, 128.6 ( J = 8 Hz)]. The
1
1
2
3
1
2
3
+
structure of compound 40 was further confirmed by molecular ion peaks at m/z 387.1 (M+H) and m/z 389.1
+
(
M+H+2) (3:1). Structures of all the derivatives were ascertained similarly.
3
. Biology
3
.1. Anti-tubercular activity
The synthesized compounds (25-64) were screened for their antitubercular activity against
Mycobacterium smegmatis, which is a fast growing non-pathogenic strain to assess the activity of the
compounds in primary screening. The literature revealed that M. smegmatis based screens show 100%
specificity and 78% sensitivity in comparison to MDR M. tuberculosis [42-45]. The percentage inhibition
was determined against DMSO and compounds that showed inhibition at 30 % or more were further
subjected for MIC studies. Rifampicin and isoniazid were used as reference drugs. The results of
antitubercular activity is reported in Table 1.
3
.2. Antibacterial activity
The in vitro antibacterial activity of all the synthesized compounds was done by the disc diffusion
method against the standard Gram-positive bacteria, Bacillus subtilis (NCIM 2162), Staphylococcus aureus
NCIM 2602) and Gram-negative bacteria, Escherichia coli (NCIM 2576), Proteus vulgaris (NCIM 2813).
(
Ciprofloxacin and Amoxicillin which served as positive controls were obtained from their respective
manufacturers. The in vitro preliminary screening results (zone of inhibition) against microorganisms tested
are summarized in Table 2.
<
Table 1>
<
Table 2>
4. Result, discussion and conclusion
4
.1 Antitubercular activity
The in vitro anti-tubercular activity against M. smegmatis, revealed that compounds 26, 27, 28, 29,
0, 31, 38, 40, 44, 49, 50, 54, 55, 56, and 64 exhibited moderate to good activity with inhibition in the range
3
3

ACCEPTED MANUSCRIPT
8.0 to 88.9 %, at 30 µM concentration. The preliminary structure activity relationship study revealed that
2
replacement of hydrogen atom of phenyl ring A and B (Figure 2) by substituent groups like Br, Cl, F and
CH significantly increase the anti-tubercular activity.
3
<
Figure 2>
Further, it was also noted that, the compounds 26-31, with un-substituted phenyl ring A and
substituted phenyl ring B, all the compounds showed moderate activity whereas compounds 32-34 with
substituted benzyl ring B were found to be less active. Among the compounds 35-41with 4-chloro
substituted phenyl ring A and chloro and fluoro substituted phenyl ring B, compounds 38 and 40 showed
moderate and good activity respectively. Substitution of phenyl ring B by 4-fluoro benzyl ring in compound
4
4 showed moderate activity. Compounds 45 -51, with 4-fluorophenyl ring A and chloro or fluoro
substituted phenyl ring B, exhibited good activity. Compound 54, with 4-fluoro benzyl ring B, exhibited the
best activity among all the synthesized derivatives. Among compounds 55-61, with 4-methyl phenyl ring A
and substituted phenyl ring B, only compounds 55 and 56 showed moderate activity. When the phenyl ring
B was replaced by substituted benzyl, only compound 64 showed moderate activity.
It was noteworthy that chloro and fluoro substituents in both the rings A and B enhanced the
antitubercular activity of the derivative, particularly compound 54 with fluoro substitution in both ring A
and B was found to be the most active derivative.
The compounds that showed anti-tubercular activity (inhibition at 30 % or more) were used for an in
vitro cytotoxicity evaluation against Vero cell line. In general, the compounds tested did not show
cytotoxicity (IC50 > 80
toxicity of the compound class.
.2 Antibacterial activity
Careful analysis of the antibacterial results presented in Table 2, provides some lead molecules with
ꢀg/mL), confirming that the anti-tubercular activity does not arise from general
4
good antibacterial activity. Among the compounds 25-64 tested, it was observed that most of the derivatives
with both substituted rings showed moderate to good activity. It was worthwhile to note that compounds 44
and 54 with chloro or fluoro substituted phenyl ring A and 4-fluorobenzyl ring B exhibited excellent activity
comparable to the standard drug ciprofloxacin. It was observed that compound 54 exhibited excellent
activity even better than the standard drugs Amoxicillin and ciprofloxacin.
5
. Conclusion
In the present study, we have detailed the synthesis and evaluation of bithiazoles derivatives. It can be
concluded that, most of the synthesized compounds with Br, Cl and F substituent on either or both phenyl
rings showed moderate to good antibacterial activities. It is noteworthy that compound 54 can serve as a
4

ACCEPTED MANUSCRIPT
lead molecule as it exhibits good antitubercular as well as antimicrobial activity. Thus, these results warrant
the need for synthesis of similar libraries with other substituents to ascertain the trend described in this
work.
6. Experimental
6.1. Chemistry
All the reactions were monitored by thin layer chromatography (TLC). TLC was performed on Merck 60 F-
54 silica gel plates. Melting points were determined in capillary tubes in silicon oil bath using a Veego
2
1
13
melting point apparatus and are uncorrected. H (300 MHz) NMR and C (75 MHz) NMR spectra were
1
13
recorded on Varian mercury XL-300 and Bruker at either 400 MHz ( H NMR) and 100 MHz ( C NMR),
spectrometer instruments. Chemical shifts are reported from internal tetramethyl silane standard and are
given in δ units. Infrared spectra were recorded on Shimadzu FTIR (KBr) – 408 in KBr. The LC-MS spectra
were recorded on a Shimadzu 2010 LC-MS. Elemental analysis was performed on a Hosli CH-analyzer.
Column chromatography was performed on silica gel (100-200 mesh) supplied by Acme Chemical Co. The
chemicals and solvents used were laboratory grade and were purified as per literature methods.
6.1.1. Synthesis of 3-bromopentane-2,4-dione(2)
A mixture of acetylacetone (10 mmol) and pTSA (5 mmol) in DCM: diethylether (50 mL, 1:1) was stirred
at 0 ºC for 10 minutes, followed by NBS (10 mmol). The reaction mixture was further stirred for 1 hour at 0
ºC (TLC). The reaction was quenched by sodium bicarbonate solution and stirred for 10 minutes. The
aqueous layer was extracted with DCM and combined organic layers was washed with water, dried with
sodium sulphate and distilled under vacuum. The product isolated was used for second step without
purification.
6.1.2. General method for the synthesis of 4-methyl-2-phenylthiazole (7-10)
A mixture of thiobenzamide (6.62 mmol) and 3-bromopentane-2,4-dione, (6.62 mmol) was refluxed in
ethanol. After completion of reaction (TLC), solvent was removed under reduced pressure and the residue
was dissolved in ethyl acetate. Organic layer was washed with sodium bicarbonate and then water. Organic
layer was dried over sodium sulphate and distilled under vacuum. The product obtained was purified by
column chromatography using hexane: ethyl acetate (9:1) as eluent .
6.1.3. General method for the synthesis of 2-bromo-1-(4-methyl-2-(4-substituted phenyl)thiazol-
5
yl)ethanone (11-14)
A mixture of 1-(4-methyl-2-phenylthiazol-5-yl)ethanone (10 mmol) and pTSA (5 mmol) in DCM (50 mL)
was stirred at 0 ºC for 10 minutes. Bromine (10 mmol) in DCM (20 mL) was then added dropwise to the
reaction mixture and was further stirred for 12 hours at room temperature. After completion of the reaction,
sodium bicarbonate solution was added in reaction mixture and stirred for 10 minutes. The aqueous layer
5

ACCEPTED MANUSCRIPT
was extracted with DCM and combined organic layer was washed with water, dried over sodium sulphate
and distilled under vacuum.
6
.1.4. General method for the synthesis of 4-methyl-2-aryl-5-(2-aryl/benzylthiazol-4-yl)thiazole (25-64)
A mixture of 2-bromo-1-(2-(4-phenyl)-4-methyl thiazol-5yl)ethanone (1 mmol) and substituted thioamide
1.1 mmol) was refluxed in dry ethanol (15 mL). The reaction was monitored on TLC. After completion of
(
the reaction; reaction mixture was poured in ice water and extracted with ethyl acetate. The organic layer
was washed with sodium bicarbonate and water. The solvent was dried over sodium sulphate and removed
under vacuum. The product was purified by crystallization from ethanol.
6.1.4.1. 4-methyl-2-phenyl-5-(2-phenylthiazol-4-yl)thiazole (25)
1
Yield: 64%; mp: 194-196 ºC; H NMR (400 MHz, DMSO-d ): δ 2.71 (s, 3H, CH ), 7.46-7.54 (m, 7H, Ar-H
6
3
1
3
and Thiazole-H), 7.95-8.01 (m, 4H, Ar-H); C NMR (100 MHz, CDCl
3
): δ 17.3, 115.5, 125.8, 126.2,
1
6
6
26.4, 126.8, 129.0, 130.0, 130.4, 132.4, 133.0, 147.1, 149.6, 163.7, 166.9; Anal. Calcd for: C H N S : C,
19 14 2 2
+
8.23; H, 4.22; N, 8.38; Found: C, 68.41; H, 4.39; N, 8.53; LC-MS, m/z: 335.1 (M+H) .
.1.4.2. 5-(2-(4-bromophenyl)thiazol-4-yl)-4-methyl-2-phenylthiazole (26)
1
Yield: 68%; mp: 204-206 ºC; H NMR (300 MHz, CDCl ): δ 2.70 (s, 3H, CH ), 7.18-7.49 (m, 6H, Ar-H,
3
3
1
3
thiazole-H), 7.74-8.02 (m, 4H, Ar-H), C NMR (75 MHz, CDCl
3
): δ 16.2, 115.7, 127.0, 128.4, 128.8,
1
5
6
29.2, 129.8, 130.6, 131.9, 133.1, 137.5, 145.8, 147.5, 165.4, 167.1; Anal. Calcd for: C H BrN S : C,
19 13 2 2
+
5.21; H, 3.17; N, 6.78; Found: C, 55.39; H, 3.10; N, 6.65; LC-MS, m/z : 413.0 (M+H) .
.1.4.3. 5-(2-(3-chlorophenyl)thiazol-4-yl)-4-methyl-2-phenylthiazole (27)
1
Yield: 70%; mp: 200-202 ºC; H NMR (300 MHz, CDCl ): δ 2.94 (s, 3H, CH ), 7.41 - 7.61(m, 6H, Ar-H,
3
3
1
3
thiazole-H), 7.84 (d, J = 7.6Hz, 1H, Ar-H), 8.00 (s, 1H, Ar-H), 8.20 - 8.22 (m, 2H, Ar-H); C NMR (75
MHz, CDCl ): δ 15.9, 115.8, 124.8, 126.5, 127.4, 127.9, 129.4, 130.3, 130.6, 131.2, 132.2, 134.1, 135.1,
3
1
3
6
43.2, 146.2, 166.7, 167.9; Anal. Calcd for: C H ClN S : C, 61.86; H, 3.55; N, 7.59; Found: C, 61.97; H,
19 13 2 2
+
.60; N, 7.70; LC-MS, m/z: 369.0 (M+H) .
.1.4.4. 5-(2-(4-chlorophenyl)thiazol-4-yl)-4-methyl-2-phenylthiazole (28)
1
Yield: 72%; mp: 176-177 ºC; H NMR (300 MHz, CDCl
3
): δ 2.89 (s, 3H, CH
3
), 7.11-7.42 (m, 6H, Ar-H,
1
3
thiazole-H), 7.91 (d, J = 8.6Hz, 2H, Ar-H), 8.14-8.17 (m, 2H, Ar-H); C NMR (75 MHz, CDCl ): δ 16.1,
3
1
15.3, 127.2, 127.8, 128.2, 129.2, 129.3, 130.0, 131.1, 131.8, 136.7, 144.2, 146.5, 166.4, 167.0; Anal. Calcd
2 2
for: C19H13ClN S : C, 61.86; H, 3.55; N, 7.59; Found: C, 62.00; H, 3.63; N, 7.51; LC-MS, m/z: 369.0
+
(
M+H) .
6.1.4.5. 5-(2-(3-chloro-4-fluorophenyl)thiazol-4-yl)-4-methyl-2-phenylthiazole (29)
1
Yield: 64%; mp: 218-220 ºC; H NMR (300 MHz, CDCl ): δ 2.66 (s, 3H, CH ), 7.47-7.57 (m, 4H, Ar-H,
3
3
1
3
thiazole-H), 7.84-7.95 (m, 4H, Ar-H), 8.09 (d, J = 6.7Hz, 1H, Ar-H); C NMR (75 MHz, CDCl ): δ 17.7,
3
1
18.5, 126.3, 127.6, 128.3, 129.1, 129.6, 130.5, 131.4, 133.2, 135.3, 138.2, 144.5, 147.4, 162.2, 164.8,
6

ACCEPTED MANUSCRIPT
67.5; Anal. Calcd for: C19H12ClFN S : C, 58.98; H, 3.13; N, 7.24; Found: C, 59.08; H, 3.10; N, 7.39; LC-
2 2
1
+
MS, m/z: 387.0 (M+H) .
6.1.4.6. 5-(2-(4-fluorophenyl)thiazol-4-yl)-4-methyl-2-phenylthiazole (30)
1
Yield: 65%; mp: 162-164 ºC; H NMR (300 MHz, CDCl
3
): ): δ 2.68 (s, 3H, CH
3
), 7.18-7.31 (m, 6H, Ar-H,
1
3
thiazole-H), 7.89-8.01 (m, 4H, Ar-H); C NMR (75 MHz, CDCl ): δ 17.3, 115.5, 125.8, 126.2, 126.4,
3
1
6
6
2 2
26.8, 129.0, 130.0, 130.4, 132.4, 133.0, 147.1, 149.6, 167.7, 168.9; Anal. Calcd for: C19H13FN S : C,
+
4.75; H, 3.72; N, 7.95; Found: C, 64.89; H, 3.77; N, 8.07; LC-MS, m/z: 353.1 (M+H) .
.1.4.7. 4-methyl-2-phenyl-5-(2-p-tolylthiazol-4-yl)thiazole (31)
1
Yield: 74%; mp: 246 ºC (dec.); H NMR (300 MHz, CDCl
3
): δ 2.36 (s, 3H, CH
3
), 2.68 (s, 3H, CH
3
), 7.05-
1
3
7
1
.49 (m, 6H, Ar-H, thiazole-H), 7.87-8.19 (m, 4 H, Ar-H); C NMR (75 MHz, CDCl ): δ 17.1, 20.9, 115.6,
3
25.9, 126.2, 129.2, 129.8, 130.3, 130.9, 132.6, 134.2, 140.5, 146.6, 149.3, 163.8, 167.1; Anal. Calcd for:
+
C H N S : C, 68.93; H, 4.63; N, 8.04; Found: C, 69.07; H, 4.58; N, 8.13; LC-MS, m/z: 349.1 (M+H) .
20
16
2 2
6.1.4.8. 5-(2-benzylthiazol-4-yl)-4-methyl-2-phenylthiazole (32)
1
Yield: 60%; mp: 185-185 ºC (dec.); H NMR (300 MHz, CDCl
3
): δ 3.06 (s, 3H, CH
3
), 4.37 (s, 2H, CH
2
),
7
.29-7.42 (m, 5H, Ar-H), 7.52 (s, 1H, thiazole), 7.58-7.68 (m, 3H, Ar-H), 8.42 (d, J = 7.2Hz, 2H, Ar-H);
1
3
C NMR (75 MHz, CDCl
3
): δ 14.4, 39.4, 117.7, 125.7, 127.6, 128.4, 129.0, 129.3, 130.0, 130.8, 134.2,
1
6
6
36.8, 141.5, 142.9, 167.8, 172.3; Anal. Calcd for: C H N S : C, 68.93; H, 4.63; N, 8.04; Found: C,
2
0
16
2 2
+
9.02; H, 4.69; N, 8.11; LC-MS, m/z: 349.1 (M+H) .
.1.4.9. 5-(2-(4-chlorobenzyl)thiazol-4-yl)-4-methyl-2-phenylthiazole (33)
1
Yield: 65%; mp: 218-220 ºC; H NMR (300 MHz, CDCl ): δ 3.05 (s, 3H, CH ), 4.34 (s, 2H, CH ), 7.28-
3
3
2
1
3
7
.37 (m, 5H, Ar-H), 7.50 (s, 1H, thiazole), 7.57-7.65 (m, 2H, Ar-H), 8.40 (d, J = 7.2Hz, 2H, Ar-H);
C
NMR (75 MHz, CDCl ): δ 14.5, 38.6, 117.3, 126.1, 128.3, 129.1, 128.8, 129.9, 130.3, 133.5, 134.0, 135.2,
3
1
3
6
43.3, 144.2, 167.8, 171.3; Anal. Calcd for: C H ClN S : C, 62.73; H, 3.95; N, 7.32; Found: C, 62.85; H,
20 15 2 2
+
.87; N, 7.43; LC-MS, m/z: 383.1 (M+H) .
.1.4.10. 5-(2-(4-fluorobenzyl)thiazol-4-yl)-4-methyl-2-phenylthiazole (34)
1
Yield: 68%; mp: 200-202 ºC (dec.); H NMR (300 MHz, CDCl
3
): δ 3.03 (s, 3H, CH
3
), 4.31 (s, 2H, CH
2
),
7
8
1
4
6
.23 (t, J = 8.2Hz, 2H, Ar-H), 7.26-7.31 (m, 2H, Ar-H), 7.49 (s, 1H, thiazole), 7.52-7.61 (m, 3H, Ar-H),
1
3
.38 (d, J = 7.6Hz, 2H, Ar-H); C NMR (75 MHz, CDCl ): δ 14.4, 38.4, 115.8, 117.7, 125.5, 128.3, 129.1,
3
2 2
29.9, 130.6, 132.4, 134.1, 141.4, 142.8, 161.5, 167.8, 171.9; Anal. Calcd for: C20H15FN S : C, 65.55; H,
+
.13; N, 7.64; Found: C, 65.63; H, 4.07; N, 7.78; LC-MS, m/z: 367.1 (M+H) .
.1.4.11. 2-(4-chlorophenyl)-4-methyl-5-(2-phenylthiazol-4-yl)thiazole (35)
1
Yield: 70%; mp: 150-152 ºC; H NMR (300 MHz, DMSO-d ): δ 2.70 (s, 3H, CH ), 7.49- 7.53 (m, 5H) , Ar-
6
3
1
3
H, 7.83 (s, 1H, thiazole), 7.94-8.08 (m, 4H, Ar-H); C NMR (75 MHz, DMSO-d ): 16.0, 115.7, 127.7,
6
7

ACCEPTED MANUSCRIPT
28.6, 128.9, 129.2, 129.5, 130.8, 133.9, 139.0, 141.8, 147.6, 149.5, 166.1, 167.0; Anal. Calcd for:
1
+
C H ClN S : C, 61.86; H, 3.55; N, 7.59; Found: C, 61.98; H, 3.49; N, 7.71; LC-MS, m/z: 369.0 (M+H) .
19
13
2 2
6.1.4.12. 5-(2-(4-bromophenyl)thiazol-4-yl)-2-(4-chlorophenyl)-4-methylthiazole (36)
1
Yield: 70%; mp: 164-166 ºC; H NMR (300 MHz, CDCl
3
): 2.75 (s, 3H, CH
3
), 7.45 (d, J = 8Hz, 2H, Ar-H),
7
.59 (d, J = 8Hz, 2H, Ar-H), 7.82 (s, 1H, thiazole), 7.99 (d, J = 8Hz, 2H, Ar-H), 8.12 (d, J = 8Hz, 2H, Ar-
1
3
H); C NMR (75 MHz, CDCl
3
): δ 17.2, 114.4, 127.3, 127.6, 128.9, 129.0, 130.2, 131.3, 132.9, 135.4,
1
5
6
36.0, 147.7, 150.0, 163.2, 166.1; Anal. Calcd for: C H BrClN S : C, 50.96; H, 2.70; N, 6.26; Found: C,
19
12
2 2
+
1.10; H, 2.74; N, 6.31; LC-MS, m/z: 447.0 (M+H) .
.1.4.13. 2-(4-chlorophenyl)-5-(2-(3-chlorophenyl)thiazol-4-yl)-4-methylthiazole (37)
1
Yield: 66%; mp: 224-226 ºC; H NMR (300 MHz, CDCl ): δ 2.71 (s, 3H, CH ), 7.38-7.46 (m, 4H, Ar-H),
3
3
1
3
7
1
.68 (s, 1H, thiazole) 7.89-8.00 (m, 4H, Ar-H); C NMR (75 MHz, CDCl
3
): δ 17.1, 115.8, 127.5, 128.8,
28.9, 129.2, 129.4, 129.8, 130.5, 131.7, 133.5, 134.6, 137.0, 147.6, 150.0, 163.1 166.0 Anal. Calcd for:
+
C H Cl N S : C, 56.58; H, 3.00; N, 6.95; Found: C, 56.73; H, 3.08; N, 6.90; LC-MS, m/z: 403.0 (M+H) .
19
12
2
2 2
6.1.4.14. 2-(4-chlorophenyl)-5-(2-(4-chlorophenyl)thiazol-4-yl)-4-methylthiazole (38)
1
Yield: 68%; mp: 196-198 ºC; H NMR (300 MHz, CDCl ): δ 2.72 (s, 3H, CH ), 7.44 (d, J = 8Hz, 2H, Ar-
3
3
H), 7.51 (d, J = 8Hz, 2H, Ar-H), 7.68 (s, 1H, thiazole), 7.96 (d, J = 8Hz, 2H, Ar-H), 8.08 (d, J = 8Hz, 2H,
1
3
Ar-H); C NMR (75 MHz, CDCl ): δ 17.0, 115.9, 127.6, 128.9, 129.5, 129.8, 130.2, 130.6, 131.8, 133.9,
3
1
5
6
34.8, 147.5, 149.8, 163.0 166.1; Anal. Calcd for: C H Cl N S : C, 56.58; H, 3.00; N, 6.95; Found: C,
19 12 2 2 2
+
6.69; H, 3.11; N, 7.08; LC-MS, m/z: 403.0 (M+H) .
.1.4.15. 5-(2-(3-chloro-4-fluorophenyl)thiazol-4-yl)-2-(4-chlorophenyl)-4-methylthiazole (39)
1
Yield: 74%; mp: 198-200 ºC; H NMR (400 MHz, CDCl
3
): δ 2.69 (s, 3H, CH
3
), 7.45-7.55 (m, 3H, Ar-H),
1
3
7
.69 (m, 1H, Ar-H), 7.76 (s, 1H, thiazole), 8.05 (d, J = 8.4Hz, 2H, Ar-H), 8.11 (m, 1H, Ar-H); C NMR
(
100 MHz, CDCl ): δ 17.5, 116.1, 118.1, 125.7, 126.2, 127.8, 128.6, 129.4, 130.7, 133.4, 134.2, 134.5,
3
1
5
6
2 2 2
38.3, 148.0, 161.8, 162.4, 165.1; Anal. Calcd for: C19H11Cl FN S : C, 54.16; H, 2.63; N, 6.65; Found: C,
+
4.29; H, 2.59; N, 6.73; LC-MS, m/z: 421.0 (M+H) .
.1.4.16. 2-(4-chlorophenyl)-5-(2-(4-fluorophenyl)thiazol-4-yl)-4-methylthiazole (40)
1
Yield: 70%; mp: 140-142 ºC; H NMR (400 MHz, CDCl ): δ 2.85 (s, 3H, CH ), 7.15 (t, J = 8.4Hz, 2H, Ar-
3
3
H), 7.38 (s, 1H, thiazole), 7.42 (d, J = 8.4Hz, 2H, Ar-H), 7.96 (dd, J = 8.4 and 3.0 Hz, 2H, Ar-H), 8.04 (d, J
13
=
8.6Hz, 2H, Ar-H); C NMR (100 MHz, CDCl
3
): δ 16.3, 115.1, 116.2, 128.3, 128.6, 128.7, 129.0, 129.6,
+
1
5
6
32.0, 135.7, 146.4, 147.0, 164.5, 164.7, 167.2; LCMS:387.1 (M+H) Anal. Calcd for: C H ClFN S : C,
1
9
12
2 2
+
8.98; H, 3.13; N, 7.24; Found: C, 59.11; H, 3.17; N, 7.31; LC-MS, m/z: 387.1 (M+H) .
.1.4.17. 2-(4-chlorophenyl)-4-methyl-5-(2-p-tolylthiazol-4-yl)thiazole (41)
1
Yield: 75%; mp: 158-160 ºC; H NMR (300 MHz, CDCl ): 2.40 (s, 3H, CH ), 2.72 (s, 3H, CH ), 7.24 (d, J
3
3
3
1
3
=
8.1 Hz, 2H, Ar-H), 7.25 (s, 1H, thiazole), 7.42 (d, J = 8.1 Hz, 2H, Ar-H), 7.87-7.90 (m, 4H, Ar-H); C
8

ACCEPTED MANUSCRIPT
): δ 17.5, 21.5, 113.5, 126.5, 127.5, 129.1, 129.6, 129.9, 130.4, 132.1, 135.7, 140.7,
NMR (75 MHz, CDCl
3
1
4
6
47.9, 150.0, 163.6, 167.9 Anal. Calcd for C H ClN S : C, 62.73; H, 3.95; N, 7.32; Found: C, 62.82; H,
20 15 2 2
+
.01; N, 7.27; LC-MS, m/z: 383.0 (M+H) .
.1.4.18. 5-(2-benzylthiazol-4-yl)-2-(4-chlorophenyl)-4-methylthiazole (42)
1
Yield: 65%; mp: 100-101 ºC; H NMR (400 MHz, CDCl ): δ 2.58 (s, 3H, CH ), 4.28 (s, 2H, CH ), 7.10 (s,
3
3
2
1
3
1
H), 7.17-7.8 (m, 5H, Ar-H, thiazole-H), 7.30 (d, J = 8.4 Hz, 2H, Ar-H), 7.79 (d, J = 8.4 Hz, 2H, Ar-H); C
NMR (75 MHz, CDCl ): δ 17.4, 39.6, 114.4, 127.3, 127.5, 128.1, 128.8, 129.1, 131.3, 132.1, 135.7, 137.4,
3
1
4
6
46.9, 149.8, 163.5, 170.7; Anal. Calcd for: C H ClN S : C, 62.73; H, 3.95; N, 7.32; Found: C, 62.79; H,
20 15 2 2
+
.00; N, 7.38; LC-MS, m/z: 383.0 (M+H) .
.1.4.19. 5-(2-(4-chlorobenzyl)thiazol-4-yl)-2-(4-chlorophenyl)-4-methylthiazole (43)
1
Yield: 75%; mp: 148-150 ºC; H NMR (300 MHz, CDCl
3
): 2.67 (s, 3H, CH
3
), 4.33 (s, 2H, CH
2
), 7.21-7.43
1
3
(
m, 5H, Ar-H, thiazole-H), 7.39 (d, J = 8.5Hz, 2H, Ar-H), 7.91 (d, J = 8.5Hz, 2H, Ar-H); C NMR (75
MHz, CDCl ): δ 17.4, 38.8, 114.4, 115.6, 127.4, 129.1, 129.9, 130.6, 132.1, 133.2, 135.8, 147.1, 149.9,
3
1
2 2 2
63.6, 168.6, 169.7; Anal. Calcd for: C20H14Cl N S : C, 57.55; H, 3.38; N, 6.71; Found: C, 57.61; H, 3.44;
+
N, 6.80; LC-MS, m/z: 417.1 (M+H) .
6.1.4.20. 5-(2-(4-fluorobenzyl)thiazol-4-yl)-2-(4-chlorophenyl)-4-methylthiazole (44)
1
Yield: 68%; mp: 136-137 ºC; H NMR (300 MHz, CDCl ): 2.66 (s, 3H, CH ), 4.33 (s, 2H, CH ), 7.04 (t, J
3
3
2
=
8.5 Hz, 2H, Ar-H), 7.21 (s, 1H, thiazole), 7.32 (dd J = 8.5 and 2Hz, 2H, Ar-H), 7.39 (d, J = 8.5Hz, 2H,
1
3
Ar-H), 7.78 (d, J = 8.5Hz, 2H, Ar-H); C NMR (75 MHz, CDCl
3
): δ 17.4, 38.7, 114.4, 115.7, 127.4, 129.2,
1
5
6
30.6, 131.5, 132.1, 133.2, 135.8, 147.1, 149.8, 161.5, 163.6, 170.8; Anal. Calcd for: C H ClFN S : C,
20
14
2 2
+
9.92; H, 3.52; N, 6.99; Found: C, 60.01; H, 3.47; N, 7.10; LC-MS, m/z: 401.0 (M+H) .
.1.4.21. 2-(4-fluorophenyl)-4-methyl-5-(2-phenylthiazol-4-yl)thiazole (45)
1
Yield: 70%; mp: 178-180 ºC; H NMR (400 MHz, DMSO-d ): 2.66 (s, 3H, CH ), 7.29 (t, J = 9.1Hz, 2H,
6
3
1
3
Ar-H), 7.52-7.59 (m, 3H, Ar-H), 7.97-8.07 (m, 5H, Ar-H, thiazole-H); C NMR (100 MHz, CDCl
3
): δ 17.3,
1
13.9, 116.0, 123.4, 126.6, 128.1, 128.9, 129.9, 130.3, 134.5, 148.1, 149.9, 162.2, 163.9, 167.7; Anal. Calcd
2 2
for: C19H13FN S : C, 64.75; H, 3.72; N, 7.95; Found: C, 64.87; H, 3.79; N, 7.99; LC-MS, m/z: 353.0
+
(
M+H) .
6.1.4.22. 5-(2-(4-bromophenyl)thiazol-4-yl)-2-(4-fluorophenyl)-4-methylthiazole (46)
1
Yield: 76%; mp: 198-200 ºC; H NMR (300 MHz, CDCl
3
): δ 2.70 (s, 3H, CH
3
), 7.18 (t, J = 9.1Hz, 2H, Ar-
H), 7.48 (d, J = 8.4Hz, 2H, Ar-H), 7.68 (s, 1H, thiazole), 7.88 (m, 2H, Ar-H), 8.02 (d, J = 8.4Hz, 2H, Ar-H);
1
3
C NMR (75 MHz, CDCl
3
): δ 17.0, 115.5, 115.7, 116.1, 126.4, 127.3, 127.7, 129.2, 129.4, 131.2, 135.1,
1
47.6, 149.2, 162.5, 165.3; Anal. Calcd for: C H BrFN S : C, 52.91; H, 2.80; N, 6.49; Found: C, 53.01;
1
9
12
2 2
+
H, 2.88; N, 6.55; LC-MS, m/z: 431.0 (M+H) .
6.1.4.23. 5-(2-(3-chlorophenyl)thiazol-4-yl)-2-(4-fluorophenyl)-4-methylthiazole (47)
9

ACCEPTED MANUSCRIPT
1
Yield: 66%; mp: 218-220 ºC; H NMR (300 MHz, CDCl
H), 7.44-7.50 (m, 2H, Ar-H), 7.61 (s, 1H, thiazole), 7.89-7.94 (m, 3H, Ar-H), 8.04 (m, 1H, Ar-H); C NMR
75 MHz, CDCl ): δ 16.0, 115.9, 116.1, 127.5, 128.7, 129.0, 129.2, 129.5, 130.0, 131.1, 133.9, 136.4, 144.3,
3 3
): δ 2.69 (s, 3H, CH ), 7.16 (t, J = 8.8Hz, 2H, Ar-
1
3
(
3
1
2 2
47.8, 162.2, 166.5, 167.1; Anal. Calcd for: C19H12ClFN S : C, 58.98; H, 3.13; N, 7.24; Found: C, 59.10;
+
H, 3.10; N, 7.33; LC-MS, m/z: 387.1 (M+H) .
6.1.4.24. 5-(2-(4-chlorophenyl)thiazol-4-yl)-2-(4-fluorophenyl)-4-methylthiazole (48)
1
Yield: 70%; mp: 208-210 ºC; H NMR (300 MHz, CDCl ): δ 2.68 (s, 3H, CH ), 7.16 (t, J = 9.1Hz, 2H, Ar-
3
3
H), 7.44 (d, J = 8.4Hz, 2H, Ar-H), 7.66 (s, 1H, thiazole), 7.89 (m, 2H, Ar-H), 8.00 (d, J = 8.4Hz, 2H, Ar-H);
1
3
C NMR (75 MHz, CDCl
3
): δ 17.1, 115.6, 116.0, 126.6, 127.6, 127.8, 127.9, 129.1, 129.5, 131.1, 135.3,
1
47.2, 149.6, 162.6, 165.5; Anal. Calcd for: C H ClFN S : C, 58.98; H, 3.13; N, 7.24; Found: C, 59.13;
1
9
12
2 2
+
H, 3.19; N, 7.35; LC-MS, m/z: 387.1 (M+H) .
6.1.4.25. 5-(2-(3-chloro-4-fluorophenyl)thiazol-4-yl)-2-(4-fluorophenyl)-4-methylthiazole (49)
1
Yield: 68%; mp: 192-194 ºC; H NMR (400 MHz, DMSO-d ): δ 2.72 (s, 3H, CH ), 7.24 (t, J = 8.4Hz, 2H,
6
3
Ar-H) 7.45 (t, J = 8.44Hz, 1H, Ar-H), 7.78 (s, 1H, thiazole), 7.95- 8.02 (m, 3H, Ar-H), 8.13 (s, 1H, Ar-H);
1
3
C NMR (100 MHz, DMSO-d ): δ 17.5, 116.1, 116.4, 118.0, 125.5, 126.2, 127.7, 128.8, 129.3, 129.9,
6
1
6
6
2 2 2
30.6, 138.1, 147.6, 161.8, 162.3, 163.1, 165.6; Anal. Calcd for: C19H11ClF N S : C, 56.36; H, 2.74; N,
+
.92; Found: C, 56.38; H, 2.71; N, 7.01; LC-MS, m/z: 405.1 (M+H) .
.1.4.26. 2-(4-fluorophenyl)-5-(2-(4-fluorophenyl)thiazol-4-yl)-4-methylthiazole (50)
1
Yield: 66%; mp: 165-166 ºC; H NMR (400 MHz, CDCl
3
): δ 2.70 (s, 3H, CH
3
), 7.27-7.36 (m, 4H, Ar-H),
1
3
7
1
.86 (s, 1H, thiazole),7.99-8.06 (m, 4H, Ar-H); C NMR (100 MHz, CDCl ): δ 17.2, 115.7, 116.0, 116.2,
3
12 2 2 2
28.0, 128.4, 128.5, 129.2, 130.3, 147.0, 149.6, 161.9, 162.2, 164.4, 165.0; Anal. Calcd for: C19H F N S :
+
C, 61.60; H, 3.27; N, 7.56; Found: C, 61.78; H, 3.22; N, 7.67; LC-MS, m/z: 371.1 (M+H) .
6.1.4.27. 2-(4-fluorophenyl)-4-methyl-5-(2-p-tolylthiazol-4-yl)thiazole (51)
1
Yield: 68%; mp: 168-170 ºC; H NMR (400 MHz, DMSO-d
6
): δ 2.39 (s, 3H, CH
3
), 2.69 (s, 3H, CH
3
), 7.32
(t, J = 8.8 Hz, 2H, Ar-H), 7.34 (d, J = 8.2 Hz, 2H, Ar-H), 7.88 (d, J = 8.2 Hz, 2H, Ar-H), 7.89 (s, 1H,
1
3
thiazole), 8.00-8.03 (m, 2H, Ar-H); C NMR (100 MHz, DMSO-d
6
): δ 17.2, 21.0, 115.4, 116.2, 126.2,
1
27.0, 128.1, 129.8, 130.5, 132.2, 140.5, 146.7, 149.6, 162.6, 164.3, 167.1; Anal. Calcd for: C H FN S :
20
15
2 2
+
C, 65.55; H, 4.13; N, 7.64; Found: C, 65.67; H, 4.10; N, 7.77; LC-MS, m/z: 367.1 (M+H) .
6.1.4.28. 5-(2-benzylthiazol-4-yl)-2-(4-fluorophenyl)-4-methylthiazole (52)
1
Yield: 66%; mp: 110-112 ºC; H NMR (400 MHz, DMSO-d ): δ 2.61 (s, 3H, CH ), 4.39 (s, 2H, CH ), 7.30-
6
3
2
1
3
7
.39 (m, 7H, Ar-H), 7.72 (s, 1H, thiazole), 7.99 (dd, J = 8.4Hz and 2.0 Hz, 2H, Ar-H); C NMR (100 MHz,
CDCl ): δ 17.2, 39.4, 115.6, 116.1, 126.8, 128.7, 129.0, 129.3, 129.6, 134.7, 137.5, 146.5, 149.9, 162.2,
3
1
63.9, 167.6; Anal. Calcd for: C H FN S : C, 65.55; H, 4.13; N, 7.64; Found: C, 65.68; H, 4.08; N, 7.71;
20 15 2 2
+
LC-MS, m/z: 367.0 (M+H) .
1
0

ACCEPTED MANUSCRIPT
.1.4.29. 5-(2-(4-chlorobenzyl)thiazol-4-yl)-2-(4-fluorophenyl)-4-methylthiazole (53)
6
1
Yield: 65%; mp: 118-119 ºC; H NMR (400 MHz, CDCl ): δ 2.65 (s, 3H, CH ), 4.35 (s, 2H, CH ), 7.09 (t, J
3
3
2
1
3
=
8.6 Hz, 2H, Ar-H),7.17 (s, 1H, thiazole), 7.34 (d, J = 4.4 Hz, 4H, Ar-H), 7.90-7.93 (m, 2H, Ar-H); C
NMR (100 MHz, CDCl ): δ 17.3, 39.7, 114.4, 116.0, 127.3, 127.4, 128.3, 128.9, 129.1, 130.0, 137.5, 147.1,
49.7, 163.8, 164.0, 170.7; Anal. Calcd for: C H ClFN S : C, 59.92; H, 3.52; N, 6.99; Found: C, 60.01;
3
1
2
0
14
2 2
+
H, 3.59; N, 7.10; LC-MS, m/z: 400.0 (M+H) .
6.1.4.30. 5-(2-(4-fluorobenzyl)thiazol-4-yl)-2-(4-fluorophenyl)-4-methylthiazole (54)
1
Yield: 68%; mp:108-110 ºC; H NMR (400 MHz, DMSO-d ): δ 2.62 (s, 3H, CH ), 4.40 (s, 2H, CH ), 7.21
6
3
2
(t, J = 9.8Hz, 2H, Ar-H), 7.33 (t, J = 9.4 Hz, 2H, Ar-H),7.45 (dd, J = 8.4Hz and 3.1Hz, 2H, Ar-H), 7.75 (s,
1
3
1
1
H, thiazole),7.99 (dd, J = 8.4Hz and 2.0 Hz, 2H, Ar-H); C NMR (100 MHz, DMSO-d ): δ 17.4, 38.9,
6
14.3, 115.7, 116.0, 127.2, 128.3, 129.0, 130.7, 133.2, 147.2, 149.8, 162.6, 163.3, 134.2, 170.4; Anal. Calcd
for: C H F N S : C, 62.48; H, 3.67; N, 7.29; Found: C, 62.51; H, 3.65; N, 7.33; LC-MS, m/z: 385.0
2
0
14
2
2 2
+
(
M+H) .
6.1.4.31. 4-methyl-5-(2-phenylthiazol-4-yl)-2-p-tolylthiazole (55)
1
Yield: 72%; mp: 156-158 ºC; H NMR (400 MHz, DMSO-d ): δ 2.37 (s, 3H, CH ), 2.62 (s, 3H, CH ), 7.32
6
3
3
(d, J = 8.4Hz, 2H), 7.55-7.57 (m, 3H, Ar-H),7.86 (d, J = 8.4Hz, 2H, Ar-H), 7.97 (s, 1H, thiazole), 8.00-8.02
1
3
(
m, 2H, Ar-H); C NMR (100 MHz, DMSO-d ): δ 17.5, 21.5, 113.8, 126.3, 126.6, 126.7, 129.1, 129.6,
6
1
8
6
30.4, 131.0, 133.2, 140.2, 148.5, 149.9, 165.4, 167.7; Anal. Calcd for: C H N S : C, 68.93; H, 4.63; N,
20 16 2 2
+
.04; Found: C, 69.02; H, 4.59; N, 8.18; LC-MS, m/z: 349.0 (M+H) .
.1.4.32. 5-(2-(4-bromophenyl)thiazol-4-yl)-4-methyl-2-p-tolylthiazole (56)
1
Yield: 72%; mp: 200 ºC (dec.); H NMR (400 MHz, DMSO-d
6
): δ 2.37 (s, 3H, CH
3
), 2.68 (s, 3H, CH
3
),
7
8
1
.32 (d, J = 8.0Hz, 2H, Ar-H), 7.75 (d, J = 8.0Hz, 2H, Ar-H), 7.86 (d, J = 8.4Hz, 2H, Ar-H), 7.94 (d, J =
1
3
.4Hz, 2H, Ar-H), 8.00 (s, 1H, thiazole); C NMR (100 MHz, DMSO-d ): δ 15.9, 21.7, 115.5, 125.2, 127.4,
6
2 2
27.5, 128.1, 130.2, 131.5, 132.3, 133.2, 140.2, 148.5, 149.9, 167.1, 167.3; Anal. Calcd for: C20H15BrN S :
+
C, 56.21; H, 3.54; N, 6.55; Found: C, 56.30; H, 3.50; N, 6.47; LC-MS, m/z: 426.9 (M+H) .
6.1.4.33. 5-(2-(3-chlorophenyl)thiazol-4-yl)-4-methyl-2-p-tolylthiazole (57)
1
Yield: 66%; mp: 228-230 ºC; H NMR (400 MHz, DMSO-d ): δ 2.37 (s, 3H, CH ), 2.68 (s, 3H, CH ), 7.28-
6
3
3
1
3
7
.33 (m, 2H, Ar-H), 7.57-7.60 (m, 4H, Ar-H), 7.87 (d, J = 8.4Hz, 2H, Ar-H), 8.03 (s, 1H, thiazole);
C
6
NMR (100 MHz, DMSO-d ): 16.0, 21.6, 115.8, 127.3, 127.5, 128.4, 129.0, 129.3, 129.8, 130.0, 131.5,
1
7
6
31.8, 134.7, 139.5, 147.9, 149.6, 167.1, 167.5 δ Anal. Calcd for: C H ClN S : C, 62.73; H, 3.95; N,
20 15 2 2
+
.32; Found: C, 62.83; H, 3.99; N, 7.21; LC-MS, m/z: 383.0 (M+H) .
.1.4.34. 5-(2-(4-chlorophenyl)thiazol-4-yl)-4-methyl-2-p-tolylthiazole (58)
1
Yield: 68%; mp: 150-151 ºC; H NMR (400 MHz, DMSO-d ): δ 2.36 (s, 3H, CH ), 2.68 (s, 3H, CH ), 7.30
6
3
3
(d, J = 8.0Hz, 2H, Ar-H), 7.52 (d, J = 8.0Hz, 2H, Ar-H), 7.88 (d, J = 8.4Hz, 2H, Ar-H), 7.95 (d, J = 8.4Hz,
1
1

ACCEPTED MANUSCRIPT
3
1
2
1
6
6
H, Ar-H), 8.00 (s, 1H, thiazole); C NMR (100 MHz, DMSO-d
6
): δ 16.1, 21.5, 116.0, 127.5, 128.5, 128.8,
29.5 129.9, 132.0, 134.5, 139.8, 141.5, 147.8, 149.5, 166.9, 167.4; Anal. Calcd for: C H ClN S : C,
2
0
15
2 2
+
2.73; H, 3.95; N, 7.32; Found: C, 62.81; H, 4.00; N, 7.25; LC-MS, m/z: 383.1 (M+H) .
.1.4.35. 5-(2-(3-chloro-4-fluorophenyl)thiazol-4-yl)-4-methyl-2-p-tolylthiazole (59)
1
Yield: 65%; mp: 162-163 ºC; H NMR (400 MHz, DMSO-d ): δ 2.37 (s, 3H, CH ), 2.70 (s, 3H, CH ), 7.28-
6
3
3
1
3
7
.32 (m, 3H, Ar-H), 7.88-7.93 (m, 2H, Ar-H), 7.97-8.00 (m, 2H, Ar-H), 8.03 (s, 1H, thiazole); C NMR
(
100 MHz, DMSO-d ): δ 16.0, 21.5, 116.0, 117.4, 123.5, 126.9, 127.4, 127.6, 128.5, 129.1 129.8, 131.9,
6
1
39.5, 147.2, 149.8, 160.8, 167.0, 167.7; Anal. Calcd for: C H ClFN S : C, 59.92; H, 3.52; N, 6.99;
20 14 2 2
+
Found: C, 60.02; H, 3.44; N, 6.88; LC-MS, m/z: 400.0 (M+H) .
6.1.4.36. 5-(2-(4-fluorophenyl)thiazol-4-yl)-4-methyl-2-p-tolylthiazole (60)
1
Yield: 68%; mp: 154-156 ºC; H NMR (400 MHz, DMSO-d
6
): δ 2.37 (s, 3H, CH
3
), 2.68 (s, 3H, CH
3
), 7.32
(d, J = 8.4Hz, 2H, Ar-H), 7.40 (t, J = 8.4Hz, 2H, Ar-H), 7.86 (d, J = 7.6Hz, 2H, Ar-H), 7.97 (s, 1H,
1
3
thiazole), 8.04-8.08 (m, 2H, Ar-H); C NMR (100 MHz, DMSO-d ): δ 16.0, 21.5, 115.9, 116.1, 127.5,
6
1
2 2
28.8, 129.2 129.7, 131.7, 137.8, 139.6, 147.3, 149.7, 162.5, 166.9, 167.6; Anal. Calcd for: C20H15FN S :
+
C, 65.55; H, 4.13; N, 7.64; Found: C, 65.67; H, 4.18; N, 7.55; LC-MS, m/z: 367.0 (M+H) .
6.1.4.37. 4-methyl-2-p-tolyl-5-(2-p-tolylthiazol-4-yl)thiazole (61)
1
Yield: 70%; mp: 202-204 ºC; H NMR (400 MHz, DMSO-d ): δ 2.37 (s, 3H, CH ), 2.38 (s, 3H, CH ), 2.68
6
3
3
(
s, 3H, CH ), 7.32 (d, J = 8.4Hz, 2H, Ar-H), 7.36 (d, J = 8.4Hz, 2H, Ar-H), 7.87 (d, J = 8.4Hz, 2H, Ar-H),
3
1
3
7
1
.89 (d, J = 8.4Hz, 2H, Ar-H), 7.92 (s, 1H, thiazole); C NMR (100 MHz, DMSO-d
6
): δ 16.0, 21.4, 21.5,
16.0, 127.5, 127.7, 128.8, 129.5 129.6, 131.9, 132.0, 138.8, 138.9, 147.5, 149.5, 166.9, 167.4; Anal. Calcd
18 2 2
for: C21H N S : C, 69.58; H, 5.00; N, 7.73; Found: C, 69.55; H, 5.08; N, 7.81; LC-MS, m/z: 363.0(M +
+
H) .
6.1.4.38. 5-(2-benzylthiazol-4-yl)-4-methyl-2-p-tolylthiazole (62)
1
Yield: 60%; mp: 185-187 ºC; H NMR (400 MHz, DMSO-d
6 3 3
): δ 2.36 (s, 3H, CH ), 2.62 (s, 3H, CH ), 4.39
1
3
(
s, 2H, CH ), 7.15 (s, 1H, thiazole), 7.23-7.39 (m, 7H, Ar-H), 7.84 (d, J = 7.6Hz, 2H, Ar-H); C NMR (100
2
MHz, DMSO-d
6
): δ 15.4, 21.8, 38.6, 116.8, 125.9, 127.7, 128.6, 128.8, 129.1, 129.7, 131.9, 136.0, 141.2,
1
4
6
43.6 147.3, 167.9, 169.4; Anal. Calcd for: C H N S : C, 69.58; H, 5.00; N, 7.73; Found: C, 69.71; H,
21
18
2 2
+
.94; N, 7.65; LC-MS, m/z: 363.0 (M + H) .
.1.4.39. 5-(2-(4-chlorobenzyl)thiazol-4-yl)-4-methyl-2-p-tolylthiazole (63)
1
Yield: 66%; mp: 186-187 ºC; H NMR (400 MHz, DMSO-d ): δ 2.36 (s, 3H, CH ), 2.61 (s, 3H, CH ),
6
3
3
1
3
4
.43(s, 2H, CH
2
), 7.20-7.49 (m, 6H, Ar-H), 7.77 (s, 1H, thiazole), 7.84 (d, J = 8.0Hz, 2H, Ar-H); C NMR
(
100 MHz, DMSO-d ): δ 14.8, 21.8, 38.7, 116.9, 126.7, 128.4, 128.7, 129.3, 131.8, 131.9, 132.2, 134.8,
6
1
6
40.8, 143.1, 146.1, 168.3, 169.7; Anal. Calcd for: C H ClN S : C, 63.54; H, 4.32; N, 7.06; Found: C,
21 17 2 2
+
3.68; H, 4.24; N, 7.00; LC-MS, m/z: 397.0 (M + H) .
1
2

ACCEPTED MANUSCRIPT
.1.4.40. 5-(2-(4-fluorobenzyl)thiazol-4-yl)-4-methyl-2-p-tolylthiazole (64)
6
1
Yield: 66%; mp: 216 ºC (dec.); H NMR (400 MHz, DMSO-d ): δ 2.36 (s, 3H, CH ), 2.61 (s, 3H, CH ),
6
3
3
4
1
1
.40 (s, 2H, CH ), 7.21 (t, J = 8.8Hz, 2H, Ar-H), 7.30-7.32 (m, 2H, Ar-H), 7.43-7.46 (m, 2H, Ar-H), 7.76 (s,
2
13
6
H, thiazole), 7.84 (d, J = 8.0Hz, 2H, Ar-H); C NMR (100 MHz, DMSO-d ): δ 14.7 21.9, 38.6, 115.9,
16.8, 127.0, 128.4, 129.3, 130.5,131.8, 132.0, 140.6, 143.2 146.2, 161.5, 168.1, 169.6; Anal. Calcd for:
+
C
21
H17FN
2
S
2
: C, 66.29; H, 4.50; N, 7.36; Found: C, 66.22; H, 4.43; N, 7.51; LC-MS, m/z: 381.0 (M + H) .
6.2 Biological Method
6.2.1. Anti-tubercular activity
The compounds listed in Table 1 were screened for their antibacterial activity against
2
Mycobacterium smegmatis MC 155 strain [46]. The series of compounds were obtained in 10 mM stock
concentrations. Further, each compound was diluted with the required 100 % (v/v) DMSO to achieve a
working concentration of 1.5 mM. The inoculum for the assay was prepared by reviving a glycerol stock in
Middlebrook 7H9 broth supplemented with 0.1 % Tween 80 and 0.5 % glycerol. At the time of inoculation,
1
0 % ADS was added to the media and the culture was incubated in a shaker incubator at 37 ºC and 200
rpm. The O.D. of the inoculum reached to 0.8 - 1 approximately, a secondary inoculum was inoculated and
subsequently incubated. This was incubated overnight till the O.D. of the inoculum reached 0.4 approx.,
following which the inoculum was diluted 1:1000 times. In a 96 well microtiter plate, a 2 µL aliquot of the
1
.5 mM dilution of compound was added to each well in triplicate, to which 98 µL of inoculum dilution was
added, making the final concentration of compound 30 µM. To each plate, a set of controls was added to
better ascertain the activity of the compounds. These included DMSO, which was taken as a growth control,
and media control (Blank) and Rifampicin and Isoniazid, which were taken as positive controls of inhibition
of Mycobacterium smegmatis. After the completion of the period of 32 hours, the absorbance of the
inoculum in wells was measured at 600 nm using a Multi Mode Reader. Absorbance is considered directly
proportional to the increase in growth of bacteria. Thus, it gives a measure of the growth of bacteria in each
well. Percentage inhibition was determined against DMSO and those compounds which showed inhibition
at 30 % or more were further analyzed to determine their MIC values. In order to attain this objective, the
inhibition was tested at an increasing concentrations of compound from 6.25 µM to 100 µM. After a period
of 30 hours incubation, the absorbance of the inoculum was observed at 600 nm using a Multi Mode Reader
and the MIC values were calculated for the respective compounds. As internal standards for assay,
Rifampicin (MIC value ranges from 0.06 µg/mL) and Isoniazid (MIC value ranges from 0.03 µg/mL).
6
.2.2.Cytotoxicity activity
Vero cells were used for an in vitro cytotoxicity evaluation for the compounds using SRB assay protocols
47], each compound was tested at 4 dose levels (10, 20, 40, 80 µg/ml). Appropriate positive controls are
[
1
3

ACCEPTED MANUSCRIPT
run in each experiment and each experiment is repeated thrice. Results are given in terms of GI50, TGI and
LC50 values.
6
.2.3. Antibacterial activity
The in vitro antibacterial activity of all the synthesized compounds were done by the disc diffusion method
48, 49] against the standard strains Gram-positive bacteria, Bacillus subtilis (NCIM 2162), Staphylococcus
aureus (NCIM 2602) and Gram-negative bacteria, Escherichia coli (NCIM 2576), Proteus vulgaris (NCIM
813). All the strains were obtained from National Chemical Laboratory, Pune, India. All cultures were
[
2
maintained at 4 ºC over nutrient agar slants throughout the experiment. The cultures were incubated
overnight at 37 ºC in nutrient broth before using for antibacterial activity. Five hundred microliters of
overnight old bacterial suspension was spread over the nutrient agar plates using a sterile cotton swab in
order to get a uniform microbial growth. The synthesized compounds were dissolved in DMSO. Under
aseptic conditions, empty sterilized discs (Whatman no. 5, 6 mm diameter) were impregnated with different
concentrations (25 µg/disc, 50 µg/disc, 75 µg/disc, 100 µg/disc) of respective synthesized compounds and
placed on the agar surface. Paper disc moistened with aqueous DMSO was placed on seeded petriplates as a
vehicle control. A standard disc containing Amoxycillin and Ciprofloxacin used as positive controls were
obtained from their respective manufacturers. The plates were left for 30 min at room temperature to allow
the diffusion of synthesized compounds and then incubated at 37 ºC for 24 hours. The antimicrobial activity
was evaluated by measuring the zone of inhibition against the test of microorganism. All experiments were
carried out in triplicates.
Acknowledgements: PCM would like to thank University Grant Commission (UGC No. 42-
3
55(SR)/2013), New Delhi, India for the financial assistance and CSIR-OSDD for supporting anti-TB
activity. The Tata Institute of Fundamental Research is acknowedged for cytotoxicity activity. SAIF, Panjab
University, Chandigarh is also acknowledged for spectral analysis. YKA expresses her gratefulness to
CSIR for the financial support.
Appendix A. Supplementary data
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A list of captions
1
2
3
4
5
) Figure 1 Bithiazole natural products
) Scheme 1. Synthetic route of 25-64.
) Table 1: Antitubercular activity and cytotoxicity of compound 25-64
) Table 2: Antibacterial activity of compound 25-64
) Figure 2 Bithiazole 25-64
1
8

ACCEPTED MANUSCRIPT
Table 1: Antitubercular activity and cytotoxicity of compound 25-64
1
a
b
c
d
Comp. R
R
M. smegmatis MIC
µM
LC50 TGI
GI50 in
µ
g/mL
2
2
2
2
2
3
3
3
3
3
3
3
3
3
3
4
4
4
4
4
4
4
4
4
4
5
5
5
5
5
5
5
5
5
5
6
6
6
6
6
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
H
H
H
H
H
H
H
H
H
H
C H
4-Br C H
3-Cl C H
4-Cl C
3-Cl,4-F C H
4-F- C H
4-CH -C H
-
-
nd
nd
nd
6
5
33.5
39.1
32.4
37.9
38.8
29.6
0.8
6.1
2.3
nd
80.66
>80
>80
>80
>80
>80
nd
nd
nd
nd
nd
nd
nd
nd
nd
>80
nd
nd
nd
>80
nd
nd
nd
nd
>80
>80
nd
nd
nd
nd
nd
>80
nd
nd
nd
nd
nd
nd
>80
>80
>80
>80
>80
nd
nd
nd
nd
nd
nd
nd
nd
nd
>80
nd
nd
nd
>80
nd
nd
nd
nd
>80
>80
nd
nd
nd
nd
nd
>80
nd
nd
nd
nd
nd
nd
>80
>80
>80
>80
>80
nd
nd
nd
nd
nd
nd
nd
nd
nd
>80
nd
nd
nd
76.2
nd
nd
nd
nd
41.9
>80
nd
nd
nd
nd
nd
>80
nd
nd
nd
nd
nd
nd
6
4
69.02
81.88
71.1
62.51
91.15
>100
>100
>100
-
6
4
6
H
4
6
3
6
4
3
6
4
C
6
H
5
CH
2
4-Cl-C
4-F-C H CH
2
6
H
5
CH
2
2
2
6
5
4-Cl C H
4-Cl 4-Br C H
4-Cl 3-Cl C
4-Cl 4-Cl C H
4-Cl 3-Cl,4-F C H
4-Cl 4-F- C H
4-Cl 4-CH
4-Cl C H CH
2
6
5
nd
-
6
4
6
H
4
4
24.0
28.2
-
66.3
4.1
-
>100
74.86
-
40.73
-
6
6
3
6
4
3
-C
6 4
H
-
-
6
5
4-Cl 4-Cl-C H CH
4-Cl 4-F-C H CH
-
6
5
36.2
4.4
-
13.3
nd
49.3
56.0
19.3
21.6
26.44
88.9
29.7
33.4
-
nd
nd
23.9
-
20.5
-
74.64
>100
-
-
-
54.71
48.22
>100
>100
>100
30.38
90.99
80.81
-
6
5
2
4-F
4-F
4-F
4-F
4-F
4-F
4-F
4-F
4-F
4-F
6 5
C H
4-Br C
3-Cl C H
4-Cl C H
3-Cl,4-F C
4-F- C
4-CH -C H
6
H
4
4
4
6
6
6
H
3
6 4
H
3
6
4
C H CH
2
6
5
4-Cl-C H CH
4-F-C
6
5
6
H
5
CH
2
4-CH3 C H
4-CH3 4-Br C H
4-CH3 3-Cl C H
4-CH
4-CH
4-CH3 4-F- C H
4-CH3 4-CH -C H
4-CH
4-CH
4-CH3 4-F-C H CH
2
6
5
6
4
4
4
6
3
4-Cl C
3-Cl,4-F C
6
H
-
-
3
6
H
3
>100
-
>100
-
96.32
9.72
36.46
6
4
3
6
4
3
C
6
H
5
CH
2
3
4-Cl-C
6
H
5
CH
2
nd
nd
>80
>80
nd
nd
>80
>80
nd
nd
>80
>80
28.0
98
97
6
5
Rifampicin
Isoniazid
a: % inhibition; nd: Not determined; b: Concentration of the compound that kills 50% of the cells; c:
Concentration of the compound that produces total inhibition of the cells; d: Concentration of the
compound that produces 50% inhibition of the cells.
1

ACCEPTED MANUSCRIPT
Table 2: Antibacterial activity of compound 25-64
1
Comd. R
R
S. aureus
B. subtilis
E. coli
P. vulgaris
2
2
2
2
2
3
3
3
3
3
3
3
3
3
3
4
4
4
4
4
4
4
4
4
4
5
5
5
5
5
5
5
5
5
5
6
6
6
6
6
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
H
H
H
H
H
H
H
H
H
H
C H
4-Br C H
3-Cl C H
4-Cl C
3-Cl,4-F C
4-F- C H
4-CH -C H
-
24
22
9
7
13
8
-
-
10
-
-
8
-
-
7
10
8
-
13
9
-
-
24
-
-
22
8
8
7
-
10
8
31
8
12
7
9
10
8
10
8
-
-
24
27
8
14
8
8
-
10
8
-
-
-
-
-
7
-
-
14
-
-
-
12
-
-
16
18
8
12
-
13
10
40
-
16
8
8
8
7
10
7
7
9
40
31
6
5
14
10
12
11
14
9
-
-
-
10
-
0
11
8
14
7
-
-
14
9
-
13
-
10
10
-
10
12
24
-
14
10
9
-
9
9
10
8
6
4
6
4
6
H
4
8
6
H
3
10
12
8
10
9
18
8
-
6
4
3
6
4
C
6
H
5
CH
2
4-Cl-C
4-F-C H CH
2
6
H
5
CH
2
2
2
6
5
4-Cl C H
4-Cl 4-Br C H
4-Cl 3-Cl C
4-Cl 4-Cl C H
4-Cl 3-Cl,4-F C H
4-Cl 4-F- C H
4-Cl 4-CH
4-Cl
4-Cl 4-Cl-C H CH
6
5
6
4
6
H
4
4
8
-
6
11
21
10
12
10
26
10
9
24
-
-
16
-
14
10
37
8
22
13
-
-
8
21
10
9
12
28
26
6
3
6
4
3
-C
6 4
H
C
6
H
5
CH
2
6
5
4-Cl 4-F-C H CH
6
5
2
4-F
4-F
4-F
4-F
4-F
4-F
4-F
4-F
4-F
4-F
6 5
C H
4-Br C
3-Cl C H
4-Cl C H
3-Cl,4-F C H
4-F- C
4-CH -C H
6
H
4
4
4
6
6
6
3
6
H
4
3
6
4
C H CH
2
6
5
4-Cl-C H CH
4-F-C
6
5
6
H
5
CH
2
4-CH3 C H
4-CH3 4-Br C H
4-CH3 3-Cl C H
4-CH
4-CH
4-CH3 4-F- C H
4-CH3 4-CH -C H
4-CH3 C H CH
2
4-CH
6
5
6
4
4
4
6
3
4-Cl C
3-Cl,4-F C
6
H
3
6
H
3
6
4
3
6
4
6
5
3
4-Cl-C
6
H
5
CH
2
4-CH3 4-F-C H CH
2
10
42
28
6
5
Amoxycilin
Ciprofloxacin
Amoxycilin (100 µg/disc) and Ciprofloxacin (100 µg/disc were used as reference; synthesized
compounds (100 µg/disc).
2

ACCEPTED MANUSCRIPT
OR
O
R
O
O
N
S
S
N
N
O
S
S
O
S
N
Myxothiazole A: R = NH2
Myxothiazole Z: R = OMe
Cystothiazoles
Antifungal
S
S
O
O
N
N
H
N
O
N
NH
HO
S
N
S
O
N
N
N
S
O
N
OH
O
N
N
O
N
S
N
O
N
S
S
O
S
S
NH2
O
HN
N
OH
NH O Ph
O
Micrococcinic acid
Antibiotic
GE2270
Antibiotic
Figure 1 Bithiazole natural products

ACCEPTED MANUSCRIPT
CH3
N
S
O
O
O
O
p-TSA, NBS
Ethanol
reflux
S
NH2
+
O
0
R
DCM, 0 C
Br
2
R
1
3-6
7-10
CH3
CH3
N
N
S
Br , DCM
2
EtOH
Br
S
+
S
S
H N
2
R1
15-24
Comp R R1
rt, 24 h
R
Reflux
R
N
O
R1
1
1-14
25-64
Comp R R1
Comp R R1
Comp R
R1
2
2
2
2
2
3
3
3
3
3
5
6
7
8
9
0
1
2
3
4
H
H
H
H
H
H
H
H
H
H
C H
4-BrC H4
3-ClC H4
4-ClC H4
3-Cl,4-FC H3 39
4-FC H4
4-CH C H
35
36
37
38
Cl C H5
Cl 4-BrC H
Cl 3-ClC H
Cl 4-ClC H
45
46
47
48
F
F
F
F
F
F
F
F
F
F
C H
4-BrC H
3-ClC H
4-ClC H
3-Cl,4-FC H
4-FC H
4-CH C H
55
56
57
58
59
60
61
62
63
64
CH3 C H
6 5
CH3 4-BrC H
CH3 3-ClC H
CH3 4-ClC H
CH3 3-Cl,4-FC H
CH3 4-FC H
6 4
CH3 4-CH C H
3 6 4
CH3 C H CH
6 5 2
6
5
6
6
5
6
6
4
6
4
6
4
6
6
4
6
4
6
4
6
6
4
6
4
6
4
Cl 3-Cl,4-FC H 49
6
6
3
6
3
6
3
40
41
42
43
44
Cl 4-FC H
50
51
52
6
6
4
6
4
Cl 4-CH C H
3
6
4
3
6
2
4
3
6
4
C H CH
Cl C H CH
C H CH
6
5
2
6
5
6
5
2
4-ClC H CH
4-FC H CH
Cl 4-ClC H CH 53
4-ClC H CH
4-FC H CH
CH3 4-ClC H CH
6 4
CH3 4-FC H CH
6 4 2
6
4
2
6
4
2
6
4
2
2
Cl 4-FC H CH
54
6
4
2
6
4
2
6
4
2
Scheme 1. Synthetic route of 25-64.

ACCEPTED MANUSCRIPT
3
4
5'
N
2
1'
S
5
4
'
S
1
B
N
2'
A
3'
n
n = 0 Phenyl
n = 1 Benzyl
Figure 2 Bithiazole 25-64

ACCEPTED MANUSCRIPT
Highlights
•
•
•
A series of 2,2′-disubstituted-4,5′-bithiazolyls were synthesized
The substituents like Br, Cl, F on either or both the phenyl ring affects on activity
Compound 54 showed substantial antitubercular and antibacterial activity

ACCEPTED MANUSCRIPT
Appendix A.
Supplementary data
Synthesis and biological screening of 2'-aryl/benzyl-2-aryl-4-methyl-4',5-
bithiazolyls as possible anti-tubercular and antimicrobial agents
c
a
b
b
a
Yogita K. Abhale, Amit V. Sasane, Abhijit P. Chavan, Keshav K. Deshmukh, Sudha Sravanti Kotapalli,
c
d
b
Ramesh Ummanni, Sadikali F. Sayyad and Pravin C. Mhaske *
a
Post-Graduate Department of Chemistry and Research Centre, S. N. Arts, D. J. M. Commerce and B. N. S.
Science College, College Road, Sangamner, District Ahmednagar, India 422 605, (Affiliated to University of
Pune)
b
Post Graduate Department of Chemistry, S. P. Mandali’s Sir Parashurambhau College, Tilak Road, Pune, India
4
11 030, (Affiliated to University of Pune).
Fax: 91-020-24332479; Tel: 91-020-24331978; E-mail: mhaskepc18@gmail.com
c
Center for Chemical biology, CSIR-Indian Institute of Chemical Technology, Hyderabad,500 007, India.
Amrutvahini College of Pharmacy, Amrutnagar, P. O. Sangamner (S.K.), Tal. Sangamner, Dist. Ahmednagar,
d
Maharashtra, India 422 608, (Affiliated to University of Pune).
The spectral data of representative compounds
CH3
S
N
N
S
F
40
Cl
1
H NMR (400 MHz, CDCl
methylthiazole(40)
3
) of 2-(4-chlorophenyl)-5-(2′-(4-fluorophenyl)thiazol-4′-yl)-4-
1

ACCEPTED MANUSCRIPT
1
3
C NMR (100 MHz, CDCl ) of 2-(4-chlorophenyl)-5-(2′-(4-fluorophenyl)thiazol-4′-yl)-4-
3
methylthiazole (40)
LC-MS spectra of 2-(4-chlorophenyl)-5-(2′-(4-fluorophenyl)thiazol-4′-yl)-4-methylthiazole (40)
2

ACCEPTED MANUSCRIPT
CH3
S
S
N
N
Cl
28
1
3
H NMR (300 MHz, CDCl ) of 5-(2′-(4-chlorophenyl)thiazol-4′-yl)-4-methyl-2-phenylthiazole (28)
1
3
C NMR (75 MHz, CDCl
3
) 5-(2′-(4-chlorophenyl)thiazol-4′-yl)-4-methyl-2-phenylthiazole (28)
3

ACCEPTED MANUSCRIPT
CH3
S
S
N
N
F
30
1
H NMR (300 MHz, CDCl ) of 5-(2′-(4-fluorophenyl)thiazol-4′-yl)-4-methyl-2-phenylthiazole (30)
3
1
3
C NMR (75 MHz, CDCl ) of 5-(2′-(4-fluorophenyl)thiazol-4′-yl)-4-methyl-2-phenylthiazole (30)
3
4