Preferential reactivity of pyridylmagnesiumchloride with n,n-dialkyl arylamides over carbonitriles: Synthesis of 2-(Aroyl) pyridines

Article abstract of DOI:10.1080/00397910802594284

Reaction of 2-pyridylmagnesium chlorides with N,N-dialkyl arylamides afford exclusively 2-(aroyl) pyridines in high yields and purity without the formation of any tertiary alcohol. This method employs easily available raw materials and avoids the use of h

Full text of DOI:10.1080/00397910802594284

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Preferential Reactivity of
Pyridylmagnesiumchloride with
N,N-Dialkyl Arylamides over
Carbonitriles: Synthesis of 2-
(
Aroyl) Pyridines
a
a
G. Venkateswara Rao , B. Narayana Swamy , P.
a
a
Hareesh Kumar & G. Chandrasekara Reddy
a
Vittal Mallya Scientific Research Foundation ,
Bangalore, India
Published online: 15 Apr 2009.
To cite this article: G. Venkateswara Rao , B. Narayana Swamy , P. Hareesh Kumar &
G. Chandrasekara Reddy (2009) Preferential Reactivity of Pyridylmagnesiumchloride
with N,N-Dialkyl Arylamides over Carbonitriles: Synthesis of 2-(Aroyl) Pyridines,
Synthetic Communications: An International Journal for Rapid Communication of
Synthetic Organic Chemistry, 39:10, 1835-1846, DOI: 10.1080/00397910802594284
To link to this article: http://dx.doi.org/10.1080/00397910802594284
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1
Synthetic Communications , 39: 1835–1846, 2009
Copyright # Taylor & Francis Group, LLC
ISSN: 0039-7911 print=1532-2432 online
DOI: 10.1080/00397910802594284
Preferential Reactivity of
Pyridylmagnesiumchloride with N,N-Dialkyl
Arylamides over Carbonitriles: Synthesis of
2
-(Aroyl) Pyridines
G. Venkateswara Rao, B. Narayana Swamy, P. Hareesh Kumar,
and G. Chandrasekara Reddy
Vittal Mallya Scientific Research Foundation, Bangalore, India
Abstract: Reaction of 2-pyridylmagnesium chlorides with N,N-dialkyl arylamides
afford exclusively 2-(aroyl) pyridines in high yields and purity without the forma-
tion of any tertiary alcohol. This method employs easily available raw materials
and avoids the use of hazardous lithium reagents and cryogenic conditions.
Further, preferential reactivity of this Grignard reagent with N,N-dialkyl aryl-
amides over its carbonitrile counterparts offers a variety of 2-(aroyl) pyridines
including the ones containing carbonitrile groups on the aryl ring.
Keywords: Aroylpyridines, dialkyl arylamides, Grignard reagent, preferential
reaction, pyridylmagnesium chloride
2-(Aroyl) pyridines have received wide attention as precursors in the
synthesis of a variety of active pharmaceutical ingredients such as
[
1]
[2]
[3]
[4]
acrivastine, carbinoxamine, doxylamine, pipradral, pirmenol,
[5]
[
6]
[7]
[8]
rimiterol, triprolidine, zimeldine, and so forth. The generally
accepted method for introducing acyl groups into aromatic and
heteroaromatic rings is direct Friedel–Crafts acylation or by reacting
metallated aryl compounds with reagents such as N,N-dimethylamides,
[
N-methoxy-N-methylamides (Weinreb amides),
[
9]
10]
O-alkyl oximes
Received September 2, 2008.
Address correspondence to G. Chandrasekara Reddy, Vittal Mallya Scientific
Research Foundation, P. B. No. 406, K. R. Road, Bangalore, 560 004, India.
E-mail: gcreddy@vmsrf.org
1
835

1836
G. V. Rao et al.
[
11]
[12]
[13]
of aldehydes,
N-(ethoxymethylene)aniline,
[15]
acid chlorides,
[
nitriles, and aroyl cyanides.
14]
However, the inertness of pyridine to electrophillic substitution and
its capacity to form complexes with Lewis acids, which further decreases
electron density on the ring, make the acylation impossible without prior
structural modifications. Even after structural modification, acylation
[
16]
takes place only on the third position of the ring.
many indirect ways to make 2-(aroyl) pyridines such as Friedel–Crafts
Hence, there are
[17]
acylation using picolinoyl chloride,
constructing the pyridine from
the regiospecific electrophillic migration
reaction of N-[1-(acyloxy)alkyl]pyridinium salts using sodium bis(tri-
[18]
1
-aryl-1,2-propanedione,
[19]
methylsilyl)amide,
[
ipso acylation reactions using trimethylstannyl
20]
pyridines,
halide or pyridyllithium with aryl cyanide.
and the reaction of cyanopyridine with arylmagnesium
[
21]
Most of these methods
suffer from disadvantages such as isomer=impurity formation, poor
yields, long reaction times, cryogenic conditions, or the use of hazardous
alkyllithium reagents.
Our efforts to develop an efficient process for these antihistamines
resulted in new methods for making 2-(N-disubstituted amino) ethyltri-
[22]
phenylphosphonium bromides
and 2-(aroyl) pyridines. Herein we
report a simple method for the preparation of 2-(aroyl) pyridines (5a–l)
in high yields and purity by reacting N,N-dialkyl aryl amides (4a–l) with
pyridylmagnesium chlorides (3a–c) at room temperature (Scheme 1 and
[23]
Table 1). Song et al. have reported that 2-pyridylmagnesium chloride
3a), prepared by reacting bromo=iodopyridine with isopropylmagne-
(
sium chloride in tetrahydrofuran (THF), was much more reactive than
its lithium analog, and hence we chose this intermediate for making 2-
[
aroyl) pyridines. When we reacted 2-pyridylmagnesium chlorides with
24]
(
various carboxylic acid derivatives such as acid chlorides, carbonitriles,
Weinreb amides, and N,N-dialkyl aryl amides under different reaction
conditions to get 2-(aroyl) pyridines, we found that N,N-dialkyl
arylamides react smoothly at room temperature to offer products without
tertiary alcohol formation.
Scheme 1. Preparation of 2-(aroyl) pyridines.

Synthesis of 2-(Aroyl) Pyridines
1837
Table 1. Yields of 2-(aryol) pyridines
Pyridyl-
magnesium Disubstituted
Entry
1
chloride
amide
2-(Aroyl) pyridine
Yield (%)
88
3a
2
3
3a
3a
89
92
4
5
3a
3a
68
73
6
7
3a
3a
60
87
8
3a
91
(
Continued )

1838
G. V. Rao et al.
Table 1. Continued
Pyridyl-
magnesium Disubstituted
Entry
9
chloride
amide
2-(Aroyl) pyridine
Yield (%)
80
3a
10
3a
80
1
1
1
2
3b
3c
89
90
Unlike other alkyl and aryl magnesium halides as reported by Olah
[
9]
et al., pyridylmagnesium chlorides offer pure 2-(aroyl) pyridines with-
out any tertiary alcohols even though amides have been added to
Grignard reagent at room temperature. It appears that the intermediate
(Grignard adduct) formed during the reaction is stable enough not to
further react with one more molecule of pyridylmagnesium chloride,
thereby avoiding the formation of tertiary alcohol. Although N,N-diethyl
arylamides did not offer any advantage over N,N-dimethyl arylamides in
terms of reactivity and yields, compounds 4f, 4 h, and 4g have been pre-
pared under anhydrous conditions using diethylamine because these
amides are water soluble.
Using this methodology, we have prepared 2-aroyl pyridines contain-
ing naphthyl, thienyl, pyridyl, and substituted aryls, and the experimental
data reveal that the electron-donating or electron-withdrawing group on

Synthesis of 2-(Aroyl) Pyridines
1839
the arylamide moiety has no bearing on final ketone yields. We have also
observed that arylamides react in preference to their carbonitrile counter-
parts, and this has been demonstrated by reacting 3a with 4-cyano-N,N-
dimethylbenzamide (4i) to afford pure 2-(4-cyanobenzoyl)pyridine (5i).
While making 5i, compound 3a has been added to the amide 4i to avoid
any impurity formation. Further, all the raw materials employed are
readily available and eliminate the usage of hazardous alkyl lithium
and cryogenic conditions. Compound 5b, which is an intermediate for
triprolidine, has been prepared in multigram quantities with consistent
yield and purity. Thus, this method is commercially viable and less
cumbersome for preparation of 2-aroyl pyridines.
In conclusion, we have demonstrated an efficient approach for
the preparation of a variety of 2-(aroyl) pyridines including the ones
with cyano group on aryl ring. This method offers products with
good purity in high yields and avoids the usage of lithium reagents and
cryogenic conditions. We believe that this protocol will be useful in
synthesizing various 2-(aroyl) pyridines as building blocks in organic
synthesis.
EXPERIMENTAL
Melting points were determined on an Acro melting-point apparatus and
are uncorrected. Infrared (IR) spectra were recorded on a Thermo
1
Nicolet Fourier transform (FT)-IR instrument in KBr discs. H NMR
1
and C NMR spectra were recorded on a Bruker 200-MHz instrument.
3
All chemical shift values are reported in d units downfield from
tetramethylsilane (TMS) as internal standard. Mass spectra (MS)
TM
were recorded on a Q-TOF micro
0=6A system.
instrument with AMPS MA ꢀ
1
Experimental Procedure for 2-(Aroyl) Pyridines (5a–l)
To a stirred solution of isopropylmagnesium bromide (20% solution
in THF, 1.1 equiv), bromopyridine 1a–c (1.0 equiv) in tetrahydrofuran
ꢁ
(
THF) was added dropwise at 20–25 C under a nitrogen atmosphere.
Stirring was continued at room temperature for 1 h and then substi-
tuted aryl amide 4a–l (1.1 equiv.) was added dropwise over a period
of 1 h. The reaction mixture was then quenched with ice-cold ammo-
nium chloride solution and extracted with toluene. The toluene layer
was dried over anhydrous Na SO and evaporated to give the
2
4
product.

1840
G. V. Rao et al.
Data
-(Benzoyl) Pyridine (5a)
Compound 5a (5.1 g, 88%) was obtained from 1a (5 g, 31.6 mmol) and 4a
2
(
1
5.1 g, 34.2 mmol). IR (KBr) tmax 3058, 3004, 2923, 1666, 1577, 1446,
ꢂ1
1
404, 1311, 1280, 1245, 1161, 1091, 1045, 995, 937 cm ; H NMR
(
200 MHz, CDCl ) d ¼ 7.52 (m, 4H), 7.86 (dt, 1H, J ¼ 1.6 Hz and
3
7
2
1
.6 Hz), 8.02 (d, 2H, J ¼ 8.0 Hz), 8.07 (d, 1H, J ¼ 7.6 Hz), 8.70 (d, 1H,
1
3
.6 Hz); C NMR (50 MHz, CDCl ) d ¼ 125.1, 126.6, 128.6, 131.4,
3
33.3, 136.7, 137.5, 148.9, 155.5, 194.3; HRMS (ESþ) m=z calcd. for
þ
C H NO [M þ H] 184.0762, obs. 184.0767.
1
2
9
2
-(4-Toluoyl) Pyridine (5b)
Compound 1a in 100 mL of THF (50 g, 316 mmol) was added dropwise at
ꢁ
20–25 C to a stirred solution of isopropylmagnesium bromide (20% solu-
tion in THF (174 mL, 34.8 mmol) under a nitrogen atmosphere. After
ꢁ
stirring the reaction mixture at 20–25 C for 1 h, 4b (56 g, 343 mmol)
was added dropwise at the same temperature over a period of 1 h. The
reaction mixture was then quenched in ice-cold ammonium chloride solu-
tion and stirred at room temperature for 30 min. The mixture was
extracted with toluene (3 ꢀ 100 mL), and the combined organic layer
was dried over anhydrous Na SO and evaporated to give 5b (56 g,
2
4
8
1
9%). IR (KBr) tmax 3055, 2920, 2866, 1662, 1604, 1577, 1434, 1407,
ꢂ1
1
307, 1284, 1242, 1157, 1091, 1041, 995, 933 cm
;
H NMR
(
1
200 MHz, CDCl ) d ¼ 2.43 (s, 3H), 7.28 (d, 2H, J ¼ 8.4 Hz), 7.47 (ddd,
3
H, J ¼ 1.2 Hz, 4.8 Hz, 7.6 Hz), 7.79–8.03 (m, 4H), 8.72 (d, 1H,
3
13
J ¼ 4.4 Hz); C NMR (50 MHz, CDCl ) d ¼ 22.1, 124.9, 126.4, 129.3,
1
31.5, 134.1, 137.4, 144.2, 148.9, 155.8, 193.9; HRMS (ESþ) m=z calcd.
þ
for C H NO [M þ H] 198.0919, obs. 198.0929.
1
3
11
2
-(1-Naphthoyl) Pyridine (5c)
Compound 5c (6.8 g, 92%) was obtained from 1a (5 g, 31.6 mmol) and 4c
1
ꢁ
(
(
8
(
1
(
6.9 g, 34.6 mmol); mp 82–84 C. H NMR (200 MHz, CDCl ) d ¼ 7.48
3
m, 4H), 7.71 (d, 1H, J ¼ 7.0 Hz), 7.91 (m, 2H), 8.02 (d, 1H, J ¼ 8.0 Hz),
1
3
.16 (d, 1H, J ¼ 8.0 Hz), 8.25 (m, 1H), 8.68 (d, 1H, J ¼ 4.4 Hz); C NMR
3
50 MHz, CDCl ) d ¼ 124.1, 124.5, 125.6, 126.2, 126.5, 127.4, 128.4,
29.9, 131.2, 132.1, 133.7, 134.6, 136.9, 149.1, 155.4, 196.5; HRMS
þ
ESþ) m=z calcd. for C H NO [M þ Na] 256.0738, obs. 256.0739.
1
6
11

Synthesis of 2-(Aroyl) Pyridines
1841
2
-(2-Thienoyl) Pyridine (5d)
Compound 5d (4.1 g, 68%) was obtained from 1a (5 g, 31.6 mmol) and
compound 4d (5.3 g, 34.2 mmol). IR (KBr) tmax 3058, 3008, 2923, 2858,
1
1
643, 1581, 1504, 1465, 1434, 1407, 1357, 1307, 1284, 1245, 1149, 1084,
ꢂ1
1
045, 999, 918 cm ; H NMR (200 MHz, CDCl ) d ¼ 7.17 (dd, 1H,
3
J ¼ 4.0 Hz, 4.0 Hz), 7.45 (ddd, 1H, J ¼ 1.6 Hz, 4.8 Hz, 7.8 Hz), 7.74 (dd,
H, J ¼ 1.0 Hz, 4.0 Hz), 7.86 (dt, 1H, J ¼ 1.6 Hz, 7.8 Hz), 8.16 (d, 1H,
1
J ¼ 7.8 Hz), 8.39 (dd, 1H, J ¼ 1.0 Hz, 4.0 Hz), 8.73 (d, 1H, J ¼ 4.8 Hz);
1
3
C NMR (50 MHz, CDCl ) d ¼ 123.7, 126.6, 127.5, 136.3, 136.6,
3
1
37.0, 139.8, 148.2, 153.8, 183.4; HRMS (ESþ) m=z calcd. for
þ
C H NOS [M þ H] 190.0326, obs. 190.0315.
1
0
7
2
-(3-Thienoyl) Pyridine (5e)
Compound 5e (4.4 g, 73%) was obtained from 1a (5 g, 31.6 mmol) and
4
1
9
e (5.3 g, 34.2 mmol). IR (KBr) tmax 3124, 3055, 3004, 2923, 2853,
647, 1577, 1508, 1465, 1434, 1384, 1284, 1245, 1137, 1080, 1045,
ꢂ1
1
95, 968 cm
;
H NMR (200 MHz, CDCl ) d ¼ 7.33 (m, 1H), 7.47
3
(
m, 1H), 7.83–7.92 (m, 2H), 8.12 (d, 1H, J ¼ 8.0 Hz), 8.73 (d, 1H,
1
3
J ¼ 4.4 Hz), 8.84 (dd, 1H, J ¼ 1.0 Hz, 2.8 Hz); C NMR (50 MHz,
CDCl ) d ¼ 124.7, 125.6, 126.8, 129.8, 137.5, 140.2, 148.9, 155.6,
3
þ
1
obs. 190.0323.
86.2; HRMS (ESþ) m=z calcd. for C H NOS [M þ H] 190.0326,
1
0
7
0
2
,2 -Dipyridyl Ketone (5f)
Compound 5f (3.5 g, 60%) was obtained from 1a (5.0 g, 31.6 mmol) and 4f
(
6.1 g, 34.2 mmol). IR (KBr) tmax 3355, 3055, 3004, 2927, 1685, 1581,
ꢂ1
1
465, 1434, 1319, 1280, 1242, 1180, 1149, 1095, 1045, 995, 945 cm
;
1
H NMR (200 MHz, CDCl ) d ¼ 7.45 (ddd, 2H, J ¼ 1.0 Hz, 4.6 Hz,
3
7
(
1
.8 Hz), 7.90 (dt, 2H, J ¼ 1.6 Hz, 7.8 Hz), 8.10 (d, 2H, J ¼ 7.8 Hz), 8.76
3
1
3
d, 2H, J ¼ 4.6 Hz); C NMR (50 MHz, CDCl ) d ¼ 125.7, 126.8,
11 8 2
37.2, 149.5, 154.6, 193.4; HRMS (ESþ) m=z calcd. for C H N O
þ
[
M þ H] 185.0715, obs. 185.0710.
0
2
,3 -Dipyridyl Ketone (5g)
Compound 5 g (5.1 g, 87%) was obtained from 1a (5 g, 31.6 mmol) and 4 g
ꢁ
(
6.1 g, 34.2 mmol); mp 67–69 C. IR (KBr) tmax 3066, 3031, 3008, 2981,
2
931, 2873, 1666, 1581, 1469, 1431, 1415, 1334, 1311, 1288, 1249, 1199,

1842
G. V. Rao et al.
ꢂ1
1
1
168, 1141, 1122, 1087, 1029, 991, 941 cm
;
H NMR (200 MHz,
CDCl ) d ¼ 7.45 (dd, 1H, J ¼ 4.8 Hz, 7.8 Hz) 7.54 (ddd, 1H, J ¼ 1.0 Hz,
3
4
8
.8 Hz, 7.8 Hz), 7.95 (dt, 1H, J ¼ 1.6 Hz, 7.8 Hz), 8.16 (d, 1H J ¼ 7.8 Hz),
.43 (dt, 1H, J ¼ 1.6 Hz, 7.8 Hz), 8.74 (d, 1H, J ¼ 4.8 Hz), 8.80 (dd, 1H,
1
3
J ¼ 1.6 Hz, 4.8 Hz) and 9.39 (d, 1H, J ¼ 1.6 Hz); C NMR (50 MHz,
CDCl ) d ¼ 123.5, 125.0, 127.3, 132.4, 137.7, 138.7, 149.1, 152.6, 153.3,
3
þ
1
1
54.3, 192.6; HRMS (ESþ) m=z calcd. for C H N O [M þ H]
1
1
8
2
85.0715, obs. 185.0718.
0
2
,4 -Dipyridyl Ketone (5h)
Compound 5 h (5.3 g, 91%) was obtained from 1a (5 g, 31.6 mmol) and 4 h
ꢁ
(6.1 g, 34.2 mmol); mp 123–126 C. IR (KBr) t
3055, 3001, 2923, 1674,
max
1
9
577, 1546, 1434, 1411, 1311, 1288, 1253, 1215, 1168, 1149, 1087, 1041,
ꢂ1
1
91, 948 cm
;
H NMR (200 MHz, CDCl ) d ¼ 7.57 (ddd, 1H,
3
J ¼ 1.0 Hz, 4.8 Hz, 7.8 Hz), 7.88–7.99 (m, 3H), 8.16 (d, 1H, J ¼ 7.8 Hz),
1
3
8
.74 (d, 1H, J ¼ 4.8 Hz), 8.82 (dd, 2H, J ¼ 1.6 Hz, 4.6 Hz); C NMR
(
1
50 MHz, CDCl ) d ¼ 124.3, 125.1, 127.5, 137.8, 143.3, 149.2, 150.6,
3
þ
53.8, 192.5; HRMS (ESþ) m=z calcd. for C H N O [M þ H]
1
1
8
2
1
85.0715, obs. 185.0712.
2
-(4-Cyanobenzoyl) Pyridine (5i)
Compound 5i (5.2 g, 80%) was obtained from 1a (5 g, 31.6 mmol) and 4i
ꢁ
(6.0 g, 34.4 mmol); mp 118–121 C. IR (KBr) t
3058, 2923, 2854,
max
2
1
233, 1670, 1581, 1558, 1465, 1434, 1404, 1311, 1284, 1242, 1195,
ꢂ1
1
153, 1091, 1045, 991, 968 cm
;
H NMR (200 MHz, CDCl3)
d ¼ 7.55 (ddd, 1H, J ¼ 1.0 Hz, 4.8 Hz, 7.6 Hz), 7.79 (d, 2H, J ¼ 8.4 Hz),
7
.95 (dt, 1H, J ¼ 1.6 Hz, 7.6 Hz), 8.15 (d, 1H, J ¼ 7.6 Hz), 8.19 (d, 2H,
1
3
J ¼ 8.4 Hz), 8.72 (d, 1H, J ¼ 4.8 Hz); C NMR (50 MHz, CDCl )
3
d ¼ 116.2, 118.6, 125.2, 127.4, 131.7, 132.2, 137.8, 140.3, 149.1, 154.1,
þ
1
obs. 209.0706.
92.6; HRMS (ESþ) m=z calcd. for C H N O [M þ H] 209.0715,
13
8
2
2
-(4-Chlorobenzoyl) Pyridine (5j)
Compound 5j (5.5 g, 80%) was obtained from 1a (5 g, 31.6 mmol) and 4j
ꢁ
(6.3 g, 34.3 mmol); mp 66–69 C. IR (KBr) t
3058, 1658, 1581, 1485,
max
1
9
1
431, 1400, 1369, 1311, 1288, 1238, 1157, 1087, 1049, 1014, 995,
ꢂ1
1
64 cm ; H NMR (200 MHz, CDCl ) d ¼ 7.44–7.54 (m, 3H), 7.92 (dt,
3
H, J ¼ 1.6 Hz, 8.0 Hz), 8.07 (d, 1H, J ¼ 7.8 Hz), 8.08 (d, 2H, J ¼ 8.4 Hz),

Synthesis of 2-(Aroyl) Pyridines
1843
1
3
8
1
.72 (d, 1H, J ¼ 4.6 Hz); C NMR (50 MHz, CDCl ) d ¼ 125.1, 126.8,
3
28.8, 132.9, 134.9, 137.6, 139.8, 148.9, 155.1, 192.8; HRMS (ESþ)
þ
m=z calcd. for C H ClNO [M þ Na] 240.0192, obs. 240.0186.
1
2
8
2
-(p-Toluoyl)-6-Methylpyridine (5k)
Compound 5k (5.5 g, 89%) was obtained from 1b (5 g, 29.0 mmol) and 4b
ꢁ
(
5.2 g, 31.9 mmol); mp 62–64 C. IR (KBr) tmax 2920, 1654, 1600, 1585,
ꢂ1
1
458, 1407, 1373, 1319, 1238, 1164, 1118, 1095, 1033, 987, 948 cm
;
1
H NMR (200 MHz, CDCl ) d ¼ 2.43 (s, 3H), 2.63 (s, 3H), 7.25–7.36
3
1
3
(
(
m, 3H), 7.75 (d, 2H, J ¼ 4.4 Hz), 8.01 (d, 2H, J ¼ 8.0 Hz); C NMR
50 MHz, CDCl ) d ¼ 21.6, 24.4, 121.5, 125.5, 128.7, 131.2, 133.5,
3
1
36.9, 143.6, 154.9, 157.5, 193.5; HRMS (ESþ) m=z calcd. for
þ
C H NO [M þ Na] 234.0895, obs. 234.0899.
1
4
13
2
-(p-Toluoyl)-5-bromopyridine (5l)
Obtained 5 l (4.3 g, 90%) from 1c (5 g, 17.6 mmol) and 4b (3.1 g,
ꢁ
1
1
9
9.0 mmol); mp 84–87 C. IR (KBr) tmax 3047, 2916, 2858, 1658, 1604,
558, 1454, 1407, 1361, 1299, 1280, 1230, 1184, 1157, 1122, 1087, 1006,
ꢂ1
1
33 cm ; H NMR (200 MHz, CDCl ) d ¼ 2.43 (s, 3H), 7.29 (d, 2H,
3
1
3
J ¼ 8.0 Hz), 7.90–8.06 (m, 4H), 8.76 (d, 1H, J ¼ 2.0 Hz); C NMR
(
1
50 MHz, CDCl ) d ¼ 22.2, 124.5, 126.3, 129.4, 131.5, 133.7, 140.2,
3
þ
44.5, 150.0, 154.0, 192.8; MS (EI) m=z 275 (M ), 119 (100%).
ACKNOWLEDGMENT
We thank Dr. Anil Kush, CEO, Vittal Mallya Scientific Research
Foundation, for his encouragement.
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