Tetrabutylammonium Iodide (TBAI) Catalyzed Electrochemical C-H Bond Activation of 2-Arylated N -Methoxyamides for the Synthesis of Phenanthridinones

Article abstract of DOI:10.1055/a-1467-5585

An electrochemical method for the synthesis of phenanthridinones through constant-potential electrolysis (CPE) mediated by Bu 4 NI (TBAI) is reported. The protocol is metal and oxidant free, and proceeds with 100% current efficiency. TBAI plays a dual role as both a redox catalyst and a supporting electrolyte. The intramolecular C-H activation proceeds under mild reaction conditions and with a short reaction time through electrochemically generated amidyl radicals. The reaction has been scaled up to a gram level, showing its practicability, and the synthetic utility and applicability of the protocol have been demonstrated by a direct one-step synthesis of the bioactive compound phenaglaydon.

Full text of DOI:10.1055/a-1467-5585

SYNLETT
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Georg Thieme Verlag KG Rüdigerstraße 14, 70469 Stuttgart
2021, 32, A–E
letter
A
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K. Subramanian et al.
Letter
Synlett
Tetrabutylammonium Iodide (TBAI) Catalyzed Electrochemical
C–H Bond Activation of 2-Arylated N-Methoxyamides for the Syn-
thesis of Phenanthridinones
Kripa Subramanian
Subhash L. Yedage
Pt Cu
O
O
Kashish Sethi
O
O
N
N
R1
R1
Bhalchandra M. Bhanage*
0
0
0
0
-
0
0
0
1
-
9
5
3
8-3
3
3
9
H
TBAI
R2
R2
constant-potential
electrolysis
Department of Chemistry, Institute of Chemical Technology,
Nathalal Parekh Marg, Matunga East, Mumbai 400031, India
bm.bhanage@ictmumbai.edu.in
metal-free and oxidant-free
catalytic amount of TBAI
mild reaction conditions
short reaction time
100% current efficiency
bm.bhanage@gmail.com
scalable up to gram level
BDeMheapalaicClrhotbamrmnreed.bnsrphtaoaoMnfda.CgBihneheg@amnAgiciamustgtmarheyiuol,.mrcInobsmatit.eudteu.oinf Chemical Technology, Nathalal Parekh Marg, Matunga East, Mumbai 400031, India
Received: 31.01.2021
Accepted after revision: 25.03.2021
Published online: 25.03.2021
DOI: 10.1055/a-1467-5585; Art ID: st-2021-b0038-l
H
H
N
N
N
N
O
N
H
O
N
O
O
N
O
H
H
Abstract An electrochemical method for the synthesis of phenan-
thridinones through constant-potential electrolysis (CPE) mediated by
Bu4NI (TBAI) is reported. The protocol is metal and oxidant free, and
proceeds with 100% current efficiency. TBAI plays a dual role as both a
redox catalyst and a supporting electrolyte. The intramolecular C–H ac-
tivation proceeds under mild reaction conditions and with a short reac-
tion time through electrochemically generated amidyl radicals. The re-
action has been scaled up to a gram level, showing its practicability, and
the synthetic utility and applicability of the protocol have been demon-
strated by a direct one-step synthesis of the bioactive compound
phenaglaydon.
PJ36
Phenaglaydon
PJ34
OH
OH
OH
OH
OH
H
N
O
O
O
OH
N
NH
NH
O
O
O
N
O
H
OH
O
O
Narciclasine
PJ38
Lycoricidine
Figure 1 Examples of bioactive molecules having a phenanthridinone
skeleton
Key words tetrabutylammonium iodide, phenanthridinones, amidyl
radicals, electrochemistry, C–H bond activation, constant-potential
electrolysis
ods (Scheme 1B), and Moon et al.5 described a photocata-
lyzed (Scheme 1C) approach to the synthesis of
phenanthridinones through direct oxidative C–H amina-
tions.
Phenanthridinone scaffolds are present in many phar-
maceutically active compounds1 (Figure 1) that act as
promising steroid surrogates. Moreover, phenanthridinones
also show a broad range of other biological activities, in-
cluding antiinflammatory, antimalarial, antibacterial, anti-
HIV, immunosuppressant, and antitumor activities. In view
of the unique properties of phenanthridinones, their syn-
theses have evinced constant research interest.
Of late, phenanthridinones have been synthesized from
N-alkoxyamides by metal-catalyzed ortho arylation with
arenes, arylboronic acids, or electron-rich aromatics, fol-
lowed by intramolecular C–N bond formation (Scheme
1A).2,3
Being robust and environmentally benign, electrochem-
ical C–H bond-activation reactions have attracted wide-
spread attention in organic syntheses, where conventional
metal-catalyzed reactions have been replaced by ones in-
volving an electric current.6 In 2018, Zeng and co-workers7
reported a constant-current electrochemical method for
the generation of amidyl radicals, which were employed in
intramolecular C–H aminations to yield phenanthridin-6-
ones (Scheme 1D). However, the reaction was limited to
amides containing an N-acetyl or N-pivaloyl protecting
group and it required the presence of a stoichiometric
amount of NaBr as a mediator and, in special cases, Na2CO3
as an additive. Kehl et al. reported a synthesis of N-aryl-
phenanthridin-6-ones by anodic N–C bond formation using
directly generated amidyl radicals in 1,1,1,3,3,3-hexafluo-
roisopropanol (HFIP) as the solvent (Scheme 1D).8 In these
electrochemical methods, deprotection of the synthesized
However, taking into account the limitations of these
metal-catalyzed approaches and their negative impact on
the environment, metal-free synthetic approaches have at-
tracted increasing attention. Xue and co-workers4 simulta-
neously developed two hypervalent iodine-catalyzed meth-
© 2021. Thieme. All rights reserved. Synlett 2021, 32, A–E
Georg Thieme Verlag KG, Rüdigerstraße 14, 70469 Stuttgart, Germany

B
K. Subramanian et al.
Letter
Synlett
A: Metal-catalyzed phenanthridinone synthesis
ing as the driving force for the reaction and also controls
the selectivity toward the desired product.10 Thus, con-
trolled-potential electrolysis is considered to be more selec-
tive than controlled-current electrolysis. Bearing this in
mind, to enhance selectivity toward 2a, further optimiza-
tions were performed by using constant-potential electrol-
ysis until 2 F mol–1 of electric charge was consumed. After
optimization, a 92% yield of the desired product 2a was ob-
tained by constant-potential electrolysis at 2.5 V in the
presence of 20 mol% of TBAI as the redox catalyst and DMF
as the solvent at 70 °C (entry 2). It was noted that a further
increase in the voltage affected the selectivity toward the
desired product. Thus, lower yields of 2a were obtained at
voltages of 4.5 V (2a/3a: 36:64) and 5 V (2a/3a: 29:71).
Screening of various redox catalysts revealed that TBAI gave
the best yield (entries 5–7). An increase in the catalyst load-
ing had little effect on the yield of 2a (entry 8), whereas a
decrease in the catalyst loading increased the duration of
electrolysis (time required to achieve 2 F mol–1), even
though an appreciable yield of 2a was still obtained (entry
9). Then, various solvents were examined and DMF was
O
OMe
Ar-X / Pd(II) /
Rh(III) / Co(III)
O
N
R
OMe
N
R
H
[Refs. 2, 3]
Ar
B: Oxidants used for the synthesis of phenanthridinones
O
O
OMe
OMe
R2
i) PhI, mCPBA
N
N
R1
R1
H
ii) TBAB, PhI, CH3COOH
[Ref. 4]
R2
C: Photocatalyzed phenanthridinone synthesis
O
O
Ir[(dFCF3ppy)2bpy]PF6
NMeBu3OP(O)(OBu)2
Ar
Ar
N
N
R1
R1
H
DCE, blue LED, 60 °C
[Ref. 5]
R2
R2
D: Electrocatalyzed phenanthridinone synthesis
O
O
i) Pt–Pt or C–C
100–200 mol% NaBr
R
R
N
N
R1
R1
H
ii) C–Ni / HFIP
[Refs. 7, 8]
R2
R2
This study: TBAI-catalyzed electrochemical phenanthridinone synthesis
O
O
O
O
N
N
Pt–Cu
R1
R1
H
mediated by TBAI
constant potential
R2
R2
Table 1 Optimization of the Reaction Conditionsa
metal-free and oxidant-free
catalytic amount of TBAI
mild reaction conditions
short reaction time
100% current efficiency
scalable up to gram level
O
O
O
O
O
N
NH
N
H
TBAI, constant voltage
Pt–Cu, undivided cell
+
Scheme 1 Several synthetic routes towards phenanthridinones
2a
3a
1a
phenanthridinones to yield the pharmaceutically active
phenanthridin-6[5H]-one derivatives required additional
steps involving conventional chemical methods.
Entry
1
Variation from standard conditions
Yieldb of 2b (%)
By considering the fact that that iodine-based organic
salts are good mediators as well as supporting electrolytes
in electroorganic synthesis, we surmised that tetrabutylam-
monium iodide (TBAI) might be an ideal metal-free redox
catalyst for the synthesis of phenanthridinones.9 Further-
more, amides containing a simple methoxy directing group
appeared to be suitable and simple alternatives to those
containing pivaloyloxy or acetoxy groups previously used in
this electrochemical transformation. On the basis of these
ideas, we have developed a constant-potential electrolytic
method for the synthesis of phenanthridinones through an
intramolecular C–H amination of 2-aryl N-methoxyamides
that uses a catalytic amount of TBAI as both a mediator and
a supporting electrolyte.
Initially, N-methoxybiphenyl-2-carboxamide (1a) was
chosen as the starting material to probe various reaction
conditions for the envisioned intramolecular C–H amina-
tion reaction in an undivided cell (Table 1). To begin with,
the reaction was carried out under constant-current condi-
tions of 9 mA. We observed a decreased selectivity toward
the desired product 2a, as an appreciable amount of the de-
methoxylated product 3a was obtained along with 2a (Table
1, entry 1). It is well known that in all electrochemical reac-
tions, the applied potential plays an important role by act-
constant current of 9 mA instead of a constant
voltage of 2.5 V
70
2
3
–
92
36
29
86
66
70
92
84
71
65
76
92
79
71
nr
4.5 V instead of 2.5 V
5 V instead of 2.5 V
4
5
TBAB instead of TBAI
Me4NI instead of TBAI
KI instead of TBAI
6
7
8
25 mol% TBAI instead of 20 mol%
10 mol% TBAI instead of 20 mol%
MeCN instead of DMF
propylene carbonate instead of DMF
60 °C instead of 70 °C
80 °C instead of 70 °C
graphite anode instead of Pt
nickel cathode instead of Cu
no TBAI
9
10
11
12
13
14
15
16
17
no electric current
nr
a Standard reaction conditions: 1a (0.5 mmol), TBAI (20 mol%), DMF (15
mL), undivided cell, Pt plate anode and Cu plate cathode (each of dimen-
sions 3 × 1.5 cm), 70 °C, 2.5 V, 2 F mol–1
.
b Determined by GC/MS; nr = no reaction.
© 2021. Thieme. All rights reserved. Synlett 2021, 32, A–E

C
K. Subramanian et al.
Letter
Synlett
found to be optimal (entries 10 and 11). A lower tempera-
ture of 60 °C gave a lower yield due to a lower conversion,
whereas a higher temperature of 80 °C did not affect the
yield of 2a (entries 12 and 13). Changing the electrode ma-
terials also adversely affected the yield and selectivity to-
ward 2a (entries 14 and 15). Note that the reaction pro-
gressed only in the presence of the redox catalyst, and that
passage of an electric current was essential for the reaction
to occur (entries 16 and 17).
With the optimized conditions in hand, we investigated
the scope of the reaction for 2-arylated N-methoxyamides
bearing various functionalities on the two phenyl rings. Ini-
tially, various substituents on Ar1 were screened (Scheme
2). Electrochemical C–H amination of N-methoxybiphenyl-
2-carboxamide (1a) gave phenanthridinone 2a in 90% yield.
Both electron-withdrawing and electron-donating substit-
uents were tolerated and moderate to good yields of the
corresponding phenanthridinones were obtained. Sub-
strates with a weakly electron-withdrawing chloro group in
the para- or meta-position gave the corresponding products
2b and 2c in yields of 79 and 72%, respectively. A stronger
methoxycarbonyl group was also tolerated, giving 2d in 66%
yield. Substrates with an electron-donating methyl or me-
thoxy group were successfully converted into the corre-
sponding phenanthridinones 2e and 2f. Remarkably, a
disubstituted amide was also converted into the corre-
sponding product 2g in good yield (84%). Unfortunately, he-
teroatom-bearing amides were stable to electrolysis and
consequently did not yield corresponding phenanthridi-
nones 2h and 2i.
After monitoring the effect of substituents on the Ar1
ring, we next focused our attention on the effect of substit-
uents on the Ar2 ring (Scheme 3). Substrates with Ar2 bear-
ing electron-donating or electron-withdrawing groups
were easily converted into the corresponding products 4a–
g in good yields. Interestingly, substrates with Ar2 bearing
- or -N-methoxynaphthamide moieties were also suc-
cessfully converted into the analogous phenanthridinones
4h and 4i.
O
O
OMe
OMe
N
NH
Ar2
Ar2
Pt–Cu, 2.5 V, ~5 h, 70 °C
TBAI (20 mol%), DMF (15 mL)
4a–i
3a–i
O
O
O
OMe
N
OMe
OMe
N
N
4a; 89%
4c; 78%
4b; 87%
O
O
O
N
Cl
OMe
OMe
OMe
N
N
Cl
MeO
4f; 83%
4d; 86%
4e; 81%
O
O
OMe
OMe
NH
O
O
O
N
Pt–Cu, 2.5 V, ~5 h, 70 °C
OMe
OMe
OMe
TBAI (20 mol%), DMF(15 mL)
N
N
N
Ar1
Ar1
Br
1a–i
2a–i
4g; 80%
O
4i; 68%
4h; 74%
O
O
OMe
OMe
OMe
N
N
Scheme 3 Scope of N-methoxybenzamides 3a–i with substituents on
ring Ar2. Reagents and conditions: N-methoxybenzamide 3a–i (0.5
mmol), TBAI (20 mol%), DMF (15 mL), Pt and Cu electrodes, undivided
cell, 2.5 V, 70 °C, ~5 h. Electrolyzed until 2 F mol–1 of electric charge
was consumed. Yields of the isolated pure products are reported.
N
Cl
Cl
2c; 72%
2a; 90%
2b; 79%
O
N
O
O
OMe
OMe
N
OMe
N
Subsequently, several control experiments were carried
out under the standard reaction conditions (Scheme 4). We
found that primary and tertiary amides did not undergo C–
H amination to yield the corresponding products (Scheme
4a) and the starting materials were recovered. Only second-
ary amides bearing an N-OR group, for example an N-OMe
group, were tolerated. We therefore concluded that an
N−OMe group is necessary for the reaction to be viable.
Further, to obtain insights into the reaction mechanism, the
electrolysis was performed under standard conditions in
the presence of 40 mol% of (2,2,6,6-tetramethylpiperidin-1-
yl)oxyl (TEMPO) as a radical scavenger. Only a trace of prod-
uct 2a was isolated (Scheme 4b), indicating that the reac-
tion proceeds by a radical mechanism.
COOMe
OMe
2d; 66%
2f; 71%
2e; 82%
O
O
O
OMe
OMe
OMe
N
N
N
S
N
2g; 84%
2h; 0%
2i; 0%
Scheme 2 Scope of N-methoxybenzamides 1a–i with substituents on
ring Ar1. Reagents and conditions: N-methoxybenzamide 1a–i (0.5
mmol), TBAI (20 mol%), DMF (15 mL), Pt and Cu electrodes, undivided
cell, 2.5 V, 70 °C, ~5 h. Electrolyzed until 2 F mol–1 of electric charge
was consumed. Yields of the isolated pure products are reported.
© 2021. Thieme. All rights reserved. Synlett 2021, 32, A–E

D
K. Subramanian et al.
Letter
Synlett
R1
R2
O
O
O
N
OMe
OMe
Pt–Cu, 2.5 V
TBAI (20 mol%), DMF (150 mL)
Pt–Cu, 2.5 V
TBAI (20 mol%), DMF (15 mL)
N
N
H
a)
no reaction
70 °C, ~5 h
70 °C, ~5 h
R1 = R2 = H
7 mmol (1.6 g)
R1 = R2 = Me
2a, 69% (1.1 g)
1a
R1 = H, R2 = Me
Scheme 6 Electrochemical gram-scale synthesis of 5-methoxyphenan-
thridin-6(5H)-one
O
O
OMe
Pt–Cu, 2.5 V
TBAI (20 mol%), TEMPO (40 mol%)
OMe
N
H
N
b)
DMF (15 mL), 70 °C
with liberation of HI, which further undergoes oxidation to
produce an iodide ion and H+, continuing the catalytic cycle.
Finally, the radical intermediate II undergoes rearomatiza-
tion and is transformed into product 2a by the loss of an
electron and a proton. At a higher applied potential, 2a ac-
quires an electron from the cathode and is converted into a
radical anion intermediate III, which undergoes cleavage to
form anion IV and a methoxy radical. Finally, anion IV is
protonated to form the demethoxylated product 5a, and the
methoxy radical eventually forms methanol.
1a
2a, < 9%
Scheme 4 Control experiments
Next, we extended our electrochemical method to syn-
theses of the natural product phenaglaydon (4j) and
phenanthridin-6(5H)-one (5a), a key intermediate in the
synthesis of PJ34 (Scheme 5).11 Unlike the method reported
by Zeng and co-workers,7 we have developed a direct sin-
gle-step electrochemical method for the synthesis of the
deprotected products by a slight modification of the stan-
dard procedure, in particular by altering the applied poten-
tial. Thus N-methoxy-5-methylbiphenyl-2-carboxamide
(3j) was electrolyzed in the presence of 30 mol% of TBAI at
5.0 V for four hours to give the deprotected and demethox-
ylated product phenaglaydon (4j) directly in 93% yield. A
similar protocol was followed in a synthesis of phenanthri-
din-6(5H)-one (5a) in 95% yield.
O
OMe
N
1a
I
A
N
O
D
E
I
I–
6-endo-trig
HI
O
O
OMe
H
OMe
N
N
– e–
– H+
II
2a
O
O
OMe
Pt–Cu, 5.0 V
TBAI (30 mol%), DMF (15 mL)
N
H
NH
O
O
80 °C, 4 h
OMe
N–
N
+
OMe
3j
4j, 93%
phenaglaydon
C
A
T
H
O
D
E
IV
III
e–
O
O
e–
H+
OMe
Pt–Cu, 5.0 V
TBAI (30 mol%), DMF (15 mL)
N
H
NH
O
2a
H+
MeO–
MeOH
80 °C, 4 h
NH
1a
5a, 95%
phenanthridin-6(5H)-one
5a
Scheme 5 Synthesis of biologically active phenanthridinones
Scheme 7 Plausible reaction mechanism
In an attempt to establish the practicality of the proto-
col, the electrochemical C–H amination of N-methoxybi-
phenyl-2-carboxamide (1a) was scaled up to a gram level,
giving a 69% yield of 5-methoxyphenanthridin-6(5H)-one
(2a) under the standard conditions, as shown in Scheme 6.
On the basis of the above observations and earlier re-
ports in the literature,7,8,12 a plausible reaction mechanism
for the electrochemical reaction is proposed, as shown in
Scheme 7. Initially, at the anode, electrochemical oxidation
of the iodide ion leads to the formation of iodine radical
that abstracts a hydrogen radical from the amide 1a to form
the amidyl radical intermediate I. This participates in a 6-
endo-trig annulation to form the radical intermediate II
In conclusion, we have developed an efficient and oper-
ationally simple electrochemical method for the intramo-
lecular C–H amination of 2-aryl N-methoxyamides for the
syntheses of phenanthridinones.13 The reaction proceeds
through the formation of highly active amidyl radicals gen-
erated by the mediator TBAI. TBAI functions as both the
electrocatalyst and the supporting electrolyte, thereby
avoiding the need to use additional conducting salts. The
reaction was performed by constant-potential electrolysis
in an undivided cell containing a platinum anode and cop-
per cathode with DMF as the solvent. This protocol exhibits
100% current efficiency with a broad substrate scope under
© 2021. Thieme. All rights reserved. Synlett 2021, 32, A–E

E
K. Subramanian et al.
Letter
Synlett
external oxidant- and transition-metal-free conditions. The
practicability of the protocol was established by scaling up
the reaction, and its synthetic utility was demonstrated by
the direct synthesis of the bioactive compound phenaglay-
don.
(6) (a) Kärkäs, M. D. Chem. Soc. Rev. 2018, 47, 5786. (b) Liang, S.; Xu,
K.; Zeng, C.-C.; Tian, H.-Y.; Sun, B.-G. Adv. Synth. Catal. 2018,
360, 4266. (c) Zhang, P.; Chen, J.; Gao, W.; Xiao, Y.; Liu, C.; Xu, S.;
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Conflict of Interest
The authors declare no conflict of interest
(9) (a) Wu, X.-F.; Gong, J.-L.; Qi, X. Org. Biomol. Chem. 2014, 12,
5807. (b) Uyanik, M.; Okamoto, H.; Yasui, T.; Ishihara, K. Science
2010, 328, 1376. (c) Finkbeiner, P.; Nachtsheim, B. J. Synthesis
2013, 45, 979. (d) Gao, W.-J.; Li, W.-C.; Zeng, C.-C.; Tian, H.-Y.;
Hu, L.-M.; Little, R. D. J. Org. Chem. 2014, 79, 9613. (e) Liang, S.;
Zeng, C. C.; Luo, X. G.; Ren, F. Z.; Tian, H. Y.; Sun, B. G.; Little, R.
D. Green Chem. 2016, 18, 2222.
Funding Information
K.S. would like to thank the University Grants Commission of India
(UGC) for providing a Senior Research Fellowship under the Basic Sci-
entific Research (BSR) program vide No. [F.25-1/2014-15, F.7-
(10) (a) Bard, A. J.; Faulkner, L. R. Electrochemical Methods: Funda-
mentals and Applications, 2nd ed; Wiley: New York, 2001.
(b) Moeller, K. D. Tetrahedron 2000, 56, 9527.
227/2009 dt. 16th Feb, 2015]
U
n
i
v
ersi
t
y
G
ra
n
t
s
C
o
m
m
i
si
o
n(F
.
2
5-1/2
0
1
4-1
5
, F
.
7-
2
2
7
/2
0
0
9
dt. 16t
h
F
e
b
, 2
0
1
5)
(11) Tu, Z.; Chu, W.; Zhang, J.; Dence, C. S.; Welch, M. J.; Mach, R. H.
Nucl. Med. Biol. 2005, 32, 437.
Supporting Information
Supporting information for this article is available online at
https://doi.org/10.1055/a-1467-5585.
(12) Syroeshkin, M. A.; Krylov, I. B.; Hughes, A. M.; Alabugin, I. V.;
Nasybullina, D. V.; Sharipov, M. Y.; Gultyai, V. P.; Terent’ev, A. O.
J. Phys. Org. Chem. 2017, 30, e3744.
S
u
p
p
orti
n
gI
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orm
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o
n
(13) 5-Methoxyphenanthridin-6(5H)-one2d (2a); Typical Proce-
dure
References and Notes
A 25 mL pear-shaped three-necked undivided cell equipped
with Pt plate anode (30 × 15 mm) and a Cu plate cathode (30 ×
15 mm) was charged with a solution of N-methoxybiphenyl-2-
carboxamide (1a; 0.5 mmol, 113.6 mg) and TBAI (0.1 mmol,
36.9 mg) in DMF (15 mL). The cell was then connected to a regu-
lated DC power supply, and constant-potential electrolysis was
carried at 2.5 V and 70 °C until 2 F mol–1 electric charge was
consumed (~5 h). The mixture was constantly stirred during the
electrolysis. The resulting mixture was diluted with EtOAc and
washed twice with H2O. The organic layers were collected,
dried (Na2SO4), filtered, and concentrated in vacuo. The crude
product was purified by column chromatography [silica gel, PE–
EtOAc (9.5:0.5)] to give a white solid; yield: 101.4 mg (90%); mp
102–104 °C.
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1H NMR (400 MHz, CDCl3):  = 8.57 (d, J = 8.1 Hz, 1 H), 8.28 (dd,
J = 8.3, 4.0 Hz, 2 H), 7.79 (t, J = 7.8 Hz, 1 H), 7.69 (d, J = 8.3 Hz, 1
H), 7.60 (q, J = 7.9, 7.4 Hz, 2 H), 7.41–7.32 (m, 1 H), 4.14 (s, 3 H).
13C NMR (100 MHz, CDCl3):  = 157.3, 135.8, 133.0, 132.6, 130.0,
128.5, 128.1, 126.3, 123.2, 121.9, 118.6, 112.6, 62.7. GC/MS (EI,
70 eV): m/z (%) = 225.0 (39.0), 195.0 (100), 180.0 (28.7), 166.05
(58.2), 152.05 (16.0), 140.05 (28.6), 83.4 (13.7), 76.0 (13.2), 40.0
(13.9).
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