Synthesis and Stereochemistry of Some New 1,3-Oxathiane Derivatives

Article abstract of DOI:10.1007/s00706-003-0090-5

The synthesis and stereochemistry of some new 2,5-substituted 1, 3-oxathiane derivatives are reported. The anancomeric or flexible structure of the derivatives and some peculiar cases of prochirality are revealed by NMR investigations.

Full text of DOI:10.1007/s00706-003-0090-5

Monatshefte f€ur Chemie 135, 89–96 (2004)
DOI 10.1007/s00706-003-0090-5
Synthesis and Stereochemistry of Some New
1,3-Oxathiane Derivatives
1
2
Mihaiela Stuparu1, Ion Grosu1;ꢀ, Luminita Muntean , Gerard Ple ,
ꢀ
´
Crina Cismas1, Anamaria Terec1, Alexandrina Nan1, and Sorin Mager1
1
‘‘Babes-Bolyai’’ University, Organic Chemistry Department and CSOFSTM, RO-3400,
Cluj-Napoca, Romania
2
ꢀ ꢀ
Universite de Rouen, IRCOF, UMR 6014, Faculte des Sciences, 76821 Mont Saint-Aignan,
Cedex, France
Received June 2, 2003; accepted June 24, 2003
Published online October 9, 2003 # Springer-Verlag 2003
Summary. The synthesis and stereochemistry of some new 2,5-substituted 1,3-oxathiane derivatives
are reported. The anancomeric or flexible structure of the derivatives and some peculiar cases of
prochirality are revealed by NMR investigations.
Keywords. Heterocycles; Conformation; Prochirality; NMR spectroscopy; Diastereotopicity.
Introduction
The stereochemistry of 1,3-oxathiane derivatives [1–5] is less studied than the
stereochemistry of 1,3-dioxanes [6–8] or 1,3-dithianes [2], [9], mainly due to
the relatively difficult access to 3-mercapto-1-propanol synthones and to the com-
plex stereochemistry of the heterocycles bearing different heteroatoms in the
ring.
The reported investigations on the stereochemistry of 1,3-oxathiane derivatives
revealed the chirality of the 1,3-oxathiane ring [1] due to the presence of a tricoor-
dinated virtual chiral center (Scheme 1, [10]).
The stereochemistry investigations of 1,3-oxathiane derivatives pointed out that
the majority of the properties of these compounds exhibit values close to the
average of the values of the same properties measured in similar 1,3-dioxane
and 1,3-dithiane derivatives [1]. The rather small number of papers on the stereo-
chemistry of the 1,3-oxathiane ring and the complex configuration and conforma-
tion behavior of this heterocycle justify the interest for investigations on the
structural aspects of some new series of derivatives.
ꢀ
Corresponding author. E-mail: igrosu@chem.ubbcluj.ro

90
M. Stuparu et al.
Scheme 1
Results and Discussions
2,5-Substituted 1,3-oxathiane derivatives 2–12 were obtained by condensation of
mercaptopropanol (1) with several aldehydes and ketones (Scheme 2).
Compounds 2 and 3 exhibit flexible structures, due to a fast flipping of the 1,3-
oxathiane ring (Scheme 3). The NMR spectra (Table 1 and Experimental) exhibit
unique signals for the axial and equatorial orientations of the protons of the hetero-
Scheme 2
Scheme 3

New 1,3-Oxathiane Derivatives
91
Table 1. 1H NMR (CDCl3, ꢁ, ppm) data for compounds 2–12
Compound
4-H
eq.
6-H
eq.
5-CH3
eq.
ax.
ax.
ax.
2
3
2.58
2.44
3.37
3.62
1.03
0.93
4
2.39
2.47
2.56
2.52
2.31
2.36
2.33
2.33
2.32
2.84
3.20
3.24
3.15
2.60
2.52
2.88
2.68
2.57
3.59
3.78
3.89
3.83
3.36
3.42
3.31
3.39
3.32
3.25
3.49
3.65
3.55
3.29
3.21
3.06
3.31
3.32
0.84
0.97
1.00
0.97
0.78
0.81
0.67
0.75
0.77
1.20
1.40
1.44
1.40
1.28
1.26
1.36
1.31
1.27
5
6
7
8
9
10
11
12
cycle or of the similar groups located on it. The flipping of the 1,3-oxathiane ring is
an enantiomeric inversion.
An interesting feature in the NMR spectra of 2 and 3 are different signals for
the methylene protons of the –CH2–R (R ¼ CH3, C6H5) groups at position 2. These
protons exhibit different signals despite the flipping of the 1,3-oxathiane ring and
despite missing a conformationally constant chiral element. Careful inspection of
structures I–IV obtained using the substitution test (Scheme 4) shows that the
replacement of a hydrogen atom at the prochiral centers ꢀ and ꢀ’ determines
besides the transformation of these centers in chiral carbon atoms, the simulta-
neous transformation of the carbon atom at position 2 in another chiral center.
Scheme 4

92
M. Stuparu et al.
Structures I–IVexhibit two chiral elements and they form two pairs of enantiomers
representing two diastereoisomers (like: I, III and unlike: II, IV). In conclu-
sion protons A and C (B and D) are enantiotopic and A or C and B or D are
diastereotopic.
1
Due to the flexibility of the heterocycle the H NMR spectrum of 3 exhibits a
singlet for the methyl groups at position 5 (ꢁMe ¼ 0.93 ppm) and splitted singlets
(doublets, due to the long range coupling with the protons of the benzyl groups;
5J ¼ 1.7 Hz) for the protons at positions 4 (ꢁ4 ¼ 2.44 ppm) and 6 (ꢁ6 ¼ 3.62 ppm).
The methylene protons of the benzyl groups exhibit two well separated doublets
of doublets (ꢁA, C ¼ 3.03; ꢁB, D ¼ 3.25 ppm) with large geminal (J ¼ 14.3 Hz)
and small long range (5J ¼ 1.7 Hz) coupling constants. The diastereotopicity
(DꢁA, C–B, D) for the 2-CH2-protons for compound 3 (Dꢁ(3) ¼ 0.22 ppm) is some-
what larger than the same difference for 2 (Dꢁ(2) ¼ 0.13 ppm).
Compounds 4–12 exhibit anancomeric structures. The conformational equilib-
ria for compounds 4–7 are shifted towards the conformer exhibiting the substitu-
ent at position 2 in equatorial orientation (V, Scheme 5) in agreement with the
high A values for alkyl and aryl groups at position 2 [11, 12] and with the results of
ROESY spectra (run with 4 and 5) that show important interactions between the
signals belonging to the proton at position 2 (axial orientation) and the signals of
the axial protons of the heterocycle (positions 4 and 6).
The conformational equilibria in 8–12 are shifted towards the conformer bear-
ing the aromatic group in axial orientation (Scheme 6). As in similar 2-alkyl,2-aryl-
1,3-dioxane derivatives the aromatic group in compounds 8–12 strongly prefers the
axial orientation. The ROESY spectra of 9 and 10 revealed weak interactions
between the axial protons of the heterocycle and the methyl group at position 2
and important interactions of the same protons with the protons of the aromatic
Scheme 5
Scheme 6

New 1,3-Oxathiane Derivatives
93
group at position 2 proving the axial orientation of the aromatic substituents at
position 2.
The NMR spectra of the compounds (Table 1) exhibit different signals for the
axial and equatorial protons of the heterocycle and for the axial and equatorial
methyl groups at position 5. As an example, the spectrum of 5 exhibits more
deshielded signals for the axial groups or protons at positions 5 and 4
(ꢁ5Me(ax) ¼ 1.40; ꢁ5Me(eq) ¼ 0.97, ꢁ4ax ¼ 3.20; ꢁ4eq ¼ 2.47 ppm) and for the equato-
rial ones at position 6 (ꢁ6ax ¼ 3.49; ꢁ6eq ¼ 3.78 ppm). The axial aromatic group
prefers the orthogonal orientation and the magnetic anisotropy of the aromatic ring
determines a shielding of the protons of the methyl group located at position 5 and
of the protons of the heterocycle.
The carbon atom at position 2 is chiral but of course 4–12 are obtained as
racemic mixtures. The conformational preference of the substituent at position 2
and the configuration of this chiral carbon atom determine the preferred configura-
tion of the heterocycle (Schemes 5 and 6).
Conclusions
The synthesis and the stereochemistry of 2,5-substituted 1,3-oxathiane derivatives
is reported. The NMR investigations reveal flexible and anancomeric structures.
The aromatic group in 2-aryl-1,3-oxathianes prefers the equatorial orientation,
while in 2-aryl,2-alkyl-derivatives the aromatic group exhibits an axial orientation.
The protons of the prochiral center of the substituents located at the position 2 in
flipping compounds are diastereotopic and show different signals in NMR spectra.
Experimental
1H and 13C NMR spectra were recorded at room temperature using CDCl3 as solvent in 5 mm tubes on
a Varian Gemini spectrometer equipped with a multinuclear head operating at 300 MHz for protons
and 75 MHz for carbon atoms. The IR spectra were recorded on a JASCO 630 FTIR spectrometer. The
EI mass spectra have been recorded at 70 eV with a GC-MSD System, Hewlett-Packard 5890 II=5972
spectrometer. Melting points were measured with a Kleinfeld melting point apparatus and are uncor-
rected. Elemental analyses (C, H, N, S) were conducted at ‘‘Babes-Bolyai’’ University using a Perkin
Elmer Analyser; their results were found to be in good agreement (ꢁ0.2%) with the calculated values.
General Procedure for the Synthesis of Compounds 2–14
Stoichiometric amounts of 11 mmol of 3-mercaptopropan-1-ol, 11mmol of carbonyl compound, and
catalytic amounts (0.05 g) of p-toluenesulfonic acid were refluxed in 20cm3 of benzene and H2O was
removed using a Dean-Stark trap. After H2O was separated and the reaction mixture was cooled to
room temperature, the catalyst was neutralized under stirring with excess of 0.1 M KOH solution. The
organic layer was washed twice with 20 cm3 of H2O. After drying (Na2SO4) the solvent was removed
and the oxathiane was purified by vacuum distillation and=or by flash-chromatography.
2,2-Diethyl-5,5-dimethyl-1,3-oxathiane (2, C10H20OS)
Yield: 45%; colorless liquid; bp 80ꢂC=2 mm Hg; 1H NMR (300MHz, CDCl3): ꢁ ¼ 0.91 (t, J ¼ 7.2 Hz,
6H, 2-CH2-CH3), 1.03 (s, 6H, 5-CH3), 1.80 (dq, J ¼ 13.5, 7.2 Hz, 2H, 2-C(H)H0-CH3), 1.93 (dq,

94
M. Stuparu et al.
J ¼ 13.5, 7.2 Hz, 2H, 2-C(H)H0-CH3), 2.58 (s, 2H, H-4), 3.37 (s, 2H, H-6) ppm; 13C NMR (75 MHz,
CDCl3): ꢁ ¼ 8.07 (2-CH2-CH3), 24.88 (5-CH3), 27.61 (C-5), 29.16 (2-CH2-CH3), 36.68 (C-4), 71.26
(C-6), 85.10 (C-2) ppm; EI-MS: m=z (%) ¼ 159 (100), 103 (16), 87 (27), 69 (40), 57 (45), 56 (20).
5,5-Dimethyl-2,2-dibenzyl-1,3-oxathiane (3, C20H24OS)
1
Yield: 44%; colorless liquid; bp 64ꢂC=1 mm Hg; H NMR (300MHz, CDCl3): ꢁ ¼ 0.93 (s, 6H, 5-
CH3), 2.44 (d, J ¼ 1.7 Hz, 2H, H-4), 3.03 (dd, J ¼ 14.3, 1.7 Hz, 2H, 2-CH(H0)), 3.25 (dd, J ¼ 14.3,
1.7 Hz, 2H, 2-CH(H0)), 3.62 (d, J ¼ 1.7 Hz, 2H, H-6), 7.30–7.52 (overlapped peaks, 10H, aromatic
protons) ppm; 13C NMR (75 MHz, CDCl3): ꢁ ¼ 24.96 (5-CH3), 28.34 (C-5), 37.07 (C-4), 44.05 (CH2),
71.97 (C-6), 85.05 (C-2), 126.54, 127.83, 130.95, 136.75 (aromatic carbon atoms) ppm; IR: ꢂꢁ¼ 1068,
1030, 799, 750, 699 cmꢃ1
.
2-(2-Propyl)-5,5-dimethyl-1,3-oxathiane (4, C9H18OS)
Yield: 60%; colorless liquid; bp 56ꢂC=2 mm Hg; 1H NMR (300MHz, CDCl3): ꢁ ¼ 0.84 (s, 3H, 5-CH3-
eq), 0.98 (d, J ¼ 6.2 Hz, 3H, CHCH3(CH3)), 1.01 (d, J ¼ 6.2Hz, 3H, CHCH3(CH3)), 1.20 (s, 3H, 5-
CH3-ax), 1.85 (heptet, J ¼ 6.2 Hz, 1H, 2-CH(CH3)2), 2.39 (dd, J ¼ 13.3, 2.2 Hz, 1H, Heq-4), 2.84 (d,
J ¼ 13.3Hz, 1H, Hax-4), 3.25 (d, J ¼ 11.5Hz, 1H, Hax-6), 3.59 (dd, J ¼ 11.5, 2.2 Hz, 1H, Heq-6), 4.42
(d, J ¼ 5.5 Hz, 1H, H-2) ppm; 13C NMR (75 MHz, CDCl3): ꢁ ¼ 18.73 (2-CH(CH3)2), 23.01 (5-CH3-
eq), 26.53 (5-CH3-ax), 28.32 (C-5), 33.54 (–CH(CH3)2), 40.14 (C-4), 80.06 (C-6), 89.43 (C-2) ppm;
EI-MS: m=z (%) ¼ 174 (14), 131 (88), 87 (11), 69 (100), 56 (23), 55 (20).
5,5-Dimethyl-2-phenyl-1,3-oxathiane (5, C12H16OS)
1
Yield: 48%; yellow crystals; mp 57.1–57.4ꢂC; H NMR (300MHz, CDCl3): ꢁ ¼ 0.97 (s, 3H, 5-CH3-
eq), 1.40 (s, 3H, 5-CH3-ax), 2.47 (dd, J ¼ 13.4, 2.3Hz, 1H, Heq-4), 3.20 (d, J ¼ 13.4Hz, 1H, Hax-4),
3.49 (d, J ¼ 11.5Hz, 1H, Hax-6), 3.78 (dd, J ¼ 11.5, 2.3 Hz, 1H, Heq-6), 5.66 (s, 1H, 2-H), 7.30–7.50
(m, 5H, aromatic protons) ppm; 13C NMR (75 MHz, CDCl3): ꢁ ¼ 23.18 (5-CH3-eq), 26.66 (5-CH3-ax),
28.12 (C-5), 41.63 (C-4), 80.25 (C-6), 84.59 (C-2), 126.34, 128.47, 128.59, 139.15 (aromatic carbon
atoms) ppm; EI-MS: m=z (%) ¼ 208 (100), 122 (24), 121 (23), 107 (27), 105 (34), 102 (96), 87 (46), 69
(90), 68 (54), 56 (74), 55 (30).
5,5-Dimethyl-2-(1-naphtyl)-1,3-oxathiane (6, C16H18OS)
Yield: 50%; white crystals; mp 150.9–151.1ꢂC; 1H NMR (300MHz, CDCl3): ꢁ ¼ 1.00 (s, 3H, 5-CH3-
eq), 1.44 (s, 3H, 5-CH3-ax), 2.56 (dd, J ¼ 13.2, 2.4Hz, 1H, Heq-4), 3.24 (d, J ¼ 13.2Hz, 1H, Hax-4),
3.65 (d, J ¼ 11.5Hz, 1H, Hax-6), 3.89 (dd, J ¼ 11.5, 2.4 Hz, 1H, Heq-6), 6.30 (s, 1H, H-2), 7.35–8.32
(overlapped peaks, 7H, aromatic protons) ppm; 13C NMR (75 MHz, CDCl3): ꢁ ¼ 23.47 (5-CH3-eq),
26.71 (5-CH3-ax), 28.44 (C-5), 41.88 (C-4), 80.80 (C-6), 82.61 (C-2), 123.41, 123.73, 124.66, 125.52,
125.74, 126.14, 128.79, 129.10, 133.74, 134.80 (aromatic carbon atoms) ppm; EI-MS: m=z (%) ¼ 258
(100), 172 (17), 157 (17), 156 (89), 155 (43), 128 (22), 127 (32), 102 (16), 69 (12).
5,5-Dimethyl-2-(2-naphtyl)-1,3-oxathiane (7, C16H18OS)
Yield: 67%; white crystals; mp 121.8–122.7ꢂC; 1H NMR (300MHz, CDCl3): ꢁ ¼ 0.97 (s, 3H, 5-CH3-
eq), 1.40 (s, 3H, 5-CH3-ax), 2.52 (dd, J ¼ 13.2, 2.4Hz, 1H, Heq-4), 3.15 (d, J ¼ 13.2Hz, 1H, Hax-4),
3.55 (d, J ¼ 11.7Hz, 1H, Hax-6), 3.83 (dd, J ¼ 11.7, 2.4 Hz, 1H, Heq-6), 5.84 (s, 1H, H-2), 7.48–7.96
(overlapped peaks, 7H, aromatic protons) ppm; 13C NMR (75 MHz, CDCl3): ꢁ ¼ 23.28 (5-CH3-eq),
26.68 (5-CH3-ax), 28.19 (C-5), 41.71 (C-4), 80.30 (C-6), 84.70 (C-2), 124.23, 125.34, 125.77, 126.28,

New 1,3-Oxathiane Derivatives
95
127.78, 128.30, 133.19, 133.44, 136.60 (aromatic carbon atoms) ppm; EI-MS: m=z (%) ¼ 258 (80),
172 (17), 171 (17), 157 (20), 156 (100), 155 (41), 129 (17), 128 (55), 127 (29), 102 (25), 69 (20), 56
(25).
2,5,5-Trimethyl-2-phenyl-1,3-oxathiane (8, C13H18OS)
1
Yield: 44%; colorless liquid; bp 110ꢂC=1 mm Hg; H NMR (300MHz, CDCl3): ꢁ ¼ 0.78 (s, 3H, 5-
CH3-eq), 1.28 (s, 3H, 5-CH3-ax), 1.72 (s, 3H, 2-CH3), 2.31 (dd, J ¼ 13.3, 2.0 Hz, 1H, Heq-4), 2.60 (d,
J ¼ 13.3Hz, 1H, Hax-4), 3.29 (d, J ¼ 11.9 Hz, 1H, Hax-6), 3.36 (dd, J ¼ 11.9, 2.0 Hz, 1H, Heq-6), 7.24–
7.76 (overlapped peaks, 5H, aromatic protons) ppm; 13C NMR (75 MHz, CDCl3): ꢁ ¼ 23.73 (5-CH3-
eq), 26.14 (5-CH3-ax), 27.68 (2-CH3), 33.11 (C-5), 38.15 (C-4), 73.21 (C-6), 85.05 (C-2), 127.03,
127.61, 128.62, 143.33 (aromatic carbon atoms) ppm; EI-MS: m=z (%) ¼ 222 (50), 207 (95), 121
(100), 105 (77), 102 (99), 87 (41), 77 (16), 66 (71), 65 (42), 56 (41), 55 (24), 51 (30).
2,5,5-Trimethyl-2-(p-nitrophenyl)-1,3-oxathiane (9, C13H17O3SN)
Yield: 63%; white crystals; mp 119.6–120.2ꢂC; 1H NMR (300MHz, CDCl3): ꢁ ¼ 0.81 (s, 3H, 5-CH3-
eq), 1.26 (s, 3H, 5-CH3-ax), 1.72 (s, 3H, 2-CH3) 2.36 (dd, J ¼ 13.4, 2.1 Hz, 1H, Heq-4), 2.52 (d,
J ¼ 13.4Hz, 1H, Hax-4), 3.21 (d, J ¼ 12.1 Hz, 1H, Hax-6), 3.42 (dd, J ¼ 12.1, 2.1Hz, 1H, Heq-6),
7.88 (d, J ¼ 8.9Hz, 2H, aromatic protons), 8.25 (d, J ¼ 8.9 Hz, 2H, aromatic protons) ppm; 13C
NMR (75 MHz, CDCl3): ꢁ ¼ 23.62 (5-CH3-eq), 25.94 (5-CH3-ax), 27.66 (2-CH3), 32.52 (C-5),
38.01 (C-4), 73.43 (C-6), 84.14 (C-2), 123.91, 128.01, 147.41, 151.28 (aromatic carbon atoms)
ppm; EI-MS: m=z (%) ¼ 267 (25), 252 (43), 102 (100), 87 (37), 74 (21), 69 (85), 68 (54), 56 (66),
55 (22).
2,5,5-Trimethyl-2-(1-naphtyl)-1,3-oxathiane (10, C17H20OS)
Yield: 67%; yellow liquid; bp 40ꢂC=0.4 mm Hg; 1H NMR (300MHz, CDCl3): ꢁ ¼ 0.67 (s, 3H, 5-CH3-
eq), 1.36 (s, 3H, 5-CH3-ax), 2.01 (s, 3H, 2-CH3), 2.33 (dd, J ¼ 13.3, 2.3 Hz, 1H, Heq-4), 2.88 (d,
J ¼ 13.3Hz, 1H, Hax-4), 3.06 (d, J ¼ 11.5 Hz, 1H, Hax-6), 3.31 (dd, J ¼ 11.5, 2.4 Hz, 1H, Heq-6), 7.35–
8.86 (overlapped peaks, 7H, aromatic protons) ppm; 13C NMR (75 MHz, CDCl3): ꢁ ¼ 23.89 (5-CH3-
eq), 26.36 (5-CH3-ax), 27.31 (2-CH3), 31.44 (C-5), 38.61 (C-4), 73.58 (C-6), 89.21 (C-2), 125.35,
125.55, 126.14, 126.40, 128.80, 129.30, 129.62, 131.23, 135.22, 136.98 (aromatic carbon atoms) ppm;
IR: ꢂꢁ: 647, 725, 778, 805, 1026, 1050, 1108, 1132, 1173 cmꢃ1
.
2,5,5-Trimethyl-2-(2-naphtyl)-1,3-oxathiane (11, C17H20OS)
Yield: 66%; colorless crystals; mp 67.3–68.4ꢂC; 1H NMR (300MHz, CDCl3): ꢁ ¼ 0.75 (s, 3H, 5-CH3-
eq), 1.31 (s, 3H, 5-CH3-ax), 1.79 (s, 3H, 2-CH3), 2.33 (dd, J ¼ 13.3, 1.9 Hz, 1H, Heq-4), 2.68 (d,
J ¼ 13.3Hz, 1H, Hax-4), 3.31 (d, J ¼ 11.9 Hz, 1H, Hax-6), 3.39 (dd, J ¼ 11.9, 2.1 Hz, 1H, Heq-6), 7.49–
8.28 (overlapped peaks, 7H, aromatic protons) ppm; 13C NMR (75 MHz, CDCl3): ꢁ ¼ 23.70 (5-CH3-
eq), 26.20 (5-CH3-ax), 27.70 (2-CH3), 33.10 (C-5), 38.25 (C-4), 73.43 (C-6), 85.30 (C-2), 124.75,
125.64, 125.76, 126.26, 127.86, 128.43, 132.94, 133.45, 140.69 (aromatic carbon atoms) ppm; EI-MS:
m=z (%) ¼ 272 (51), 257 (38), 171 (41), 170 (60), 155 (100), 127 (37).
5,5-Dimethyl-2-ethyl-2-phenyl-1,3-oxathiane (12, C14H20OS)
Yield: 72%; colorless liquid; bp 112–115ꢂC=2 mm Hg; 1H NMR (300 MHz, CDCl3): ꢁ ¼ 0.77 (s, 3H,
5-CH3-eq), 0.80 (t, J ¼ 7.3 Hz, 3H, 2-CH2-CH3), 1.27 (s, 3H, 5-CH3-ax), 1.99–2.03 (overlapped dq, 2H,
2-CH(H0)-CH3), 2.32 (d, J ¼ 13.3Hz, 1H, 4-Heq), 2.57 (d, J ¼ 13.3Hz, 1H, 4-Hax), 3.32 (s, 2H, 6-H),

96
M. Stuparu et al.: New 1,3-Oxathiane Derivatives
7.27–7.68 (m, 5H, aromatic protons) ppm; 13C NMR (75 MHz, CDCl3): ꢁ ¼ 8.45 (–CH2-CH3), 23.76
(5-CH3-eq), 26.19 (5-CH3-ax), 27.99 (C-5), 37.73 (–CH2-CH3), 38.14 (C-4), 72.94 (C-6), 89.01 (C-2),
127.52, 127.87, 128.39, 141.66 (aromatic carbon atoms) ppm; EI-MS: m=z (%) ¼ 207 (95), 135 (16),
121 (12), 105 (58), 102 (12), 77 (31), 69 (17), 57 (19).
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