Photochemical synthesis of isomeric (E/Z)-3-alkylidene-3H-isobenzofuranones

Article abstract of DOI:10.1016/j.tet.2006.11.021

The synthesis of isomeric (E/Z)-3-alkylidene-3H-isobenzofuranones by photoisomerization of 2-aroyl-2-methyl/benzylindan-1,3-diones in high yields is described.

Full text of DOI:10.1016/j.tet.2006.11.021

Tetrahedron 63 (2007) 594–597
Photochemical synthesis of isomeric (E/Z)-3-alkylidene-3H-
isobenzofuranones
b
Satbir Mor,a, Som N. Dhawan, Mona Kapoorb,y and Devinder Kumara
*
aDepartment of Chemistry, Guru Jambheshwar University of Science and Technology, Hisar-125001, Haryana, India
bDepartment of Chemistry, Kurukshetra University, Kurukshetra-136119, Haryana, India
Received 16 September 2006; revised 28 October 2006; accepted 9 November 2006
Available online 28 November 2006
Abstract—The synthesis of isomeric (E/Z)-3-alkylidene-3H-isobenzofuranones by photoisomerization of 2-aroyl-2-methyl/benzylindan-
1,3-diones in high yields is described.
Ó 2006 Elsevier Ltd. All rights reserved.
1. Introduction
2. Results and discussion
There is significant interest in the synthesis1 of naturally oc-
curring (E/Z)-3-alkylidene-3H-isobenzofuranones2 because
of their wide range of biological properties3 and use as
valuable intermediates4 in the synthesis of a variety of ring
systems. It has been reported that natural and unnatural
(Z)-3-alkylidene-3H-isobenzofuranones and 3-substituted
isocoumarins can be obtained regioselectively by cyclization
of 2-(1-alkynyl)benzoic acid by a transition metal-catalyzed
reaction.5 Furthermore, the synthesis of (E)-3-alkylidene-
3H-isobenzofuranones may be accomplished by Jones
oxidation of disubstituted alkynes (obtained from 2-iodo-
benzylalcohol and acetylenic carbinols) in the presence of
bis(triphenylphosphine)palladium (II) chloride.6
2-Aroyl-2-methyl/benzylindan-1,3-diones (2), required for
photolysis, were prepared by C-alkylation of 2-aroylindan-
1,3-dione (1) with methyl iodide/benzyl chloride in the pres-
ence of anhydrous potassium carbonate and potassium
iodide in refluxing dry acetone in 41–55% yields. Photoirra-
diation of 2 in dry benzene with a 450 W Hanovia mercury
vapor lamp under a nitrogen atmosphere in a pyrex reactor
resulted in the formation of mixture of two isomeric
products i.e. (E)-3-alkylidene-3H-isobenzofuranones (3)
(42–46%) and (Z)-3-alkylidene-3H-isobenzofuranones (4)
(44–46%), which were separated by column chromato-
graphy (Scheme 1).
The mechanism may be easily rationalized in terms of
a-cleavage (Norrish type I reaction) to generate a biradical
intermediate, which reorganizes in two ways perhaps almost
equally and readily followed by cyclization resulting in the
formation of 3 and 4 (Scheme 2).
Recently, a facile synthesis of (E/Z)-3-alkylidene-3H-
isobenzofuranones has been described, which uses the
DABCO-catalyzed Baylis–Hillman reaction of 2-carboxy-
benzaldehyde with some activated vinyl compounds.7 We
havealsoreportedthe stereoselective synthesisof(Z)-3-alkyl-
idene-3H-isobenzofuranones through photo-reorganization
of the corresponding 2-alkoxy-2-arylindane-1,3-dione.8 In
continuation of these studies, we report herein the photoiso-
merization of 2-aroyl-2-methyl/benzylindan-1,3-diones (2)
that resulted in the formation of a mixture of isomeric
(E/Z)-3-alkylidene-3H-isobenzofuranones (3 and 4) in
86–91% yields.
The structures of 2–4 were established from their physical
and spectroscopic data. The stereochemistry of E- and Z-iso-
mers was based on the IR and 1H NMR spectra as well as by
analogy with similarly constituted compounds.7 The occur-
rence of the lactone carbonyl group at 1785 cmꢀ1 and the
other conjugated carbonyl group at 1655 cmꢀ1 and similarly
bands at 1779 and 1655 cmꢀ1 were attributed to 3a and 4a,
respectively. The 1H NMR spectrum of 3a demonstrated that
the doublet of doublets due to C4-H is shielded (d 7.27) prob-
ably due to the anisotropic effect of the aryl group in
comparison to C4-H of 4a in which there is no signal in
between d 7.2 and 7.4. The spectra of 3b and 3c also illus-
trated that C4-H is shielded in comparison to C4-H of 4b
and 4c probably due to the anisotropic effect of phenyl group
Keywords: Photolysis; Indan-1,3-diones; 3-Alkylidene-3H-isobenzofura-
nones.
* Corresponding author. Fax: +91 1662 276240; e-mail addresses: satbir_
mor@yahoo.co.in; uppalmona@hotmail.com
Present address: c/o Mr. Anuj Uppal, Apt. No. 1-301, 4900 Boardwalk
y
Drive, Fort Collins, CO 80525, USA.
0040–4020/$ - see front matter Ó 2006 Elsevier Ltd. All rights reserved.
doi:10.1016/j.tet.2006.11.021

S. Mor et al. / Tetrahedron 63 (2007) 594–597
595
R1
OH
our case when photolysis of the E or Z-isomer was carried
out under similar conditions, as employed in their synthesis,
we observed the formation of a mixture of E/Z-isomers in
almost equal ratio as indicated by the H NMR spectra of
the crude photolysate and comparison with authentic sam-
ples through TLC.
R1
O
1
O
O
O
O
R2I/R2Cl
acetone
1
41-55%
R2
To study the effect of solvent, the photolysis of 2 was also
carried out in methanol. A mixture of two isomeric (E/Z)-
3-alkylidene-3H-isobenzofuranones (3 and 4) was obtained.
The only difference was that longer irradiation time (7–10 h)
was required and the reaction did not proceed to completion.
This may be due to the formation of intermolecular hydro-
gen bonding, between the starting material (2) and methanol,
resulting in an increase in the energy gap between the ground
state and the excited state and which slows down the rate of
these transformations.
R1
O
O
2
O
benzene hν
O
O
R2
R2
R1
In conclusion, the present photochemical method allows
convenient synthesis of important isomeric (E/Z)-3-alkyl-
idene-3H-isobenzofuranones (3 and 4) in high yields utiliz-
ing simple and inexpensive starting materials and is much
better than the previous methods that involve distinctive
starting materials, metal-catalyzed reaction, and more cum-
bersome experimental work-up.5–7
O
+
O
R1
O
O
4 (Z) 44-46%
3 (E) 42-46%
R1 = H, OMe, Me ; R2 = Me, CH2Ph
Scheme 1.
R1
O
R1
O
O
3. Experimental
3.1. General
R2
O
R2
O
hν
O
2
Melting points were observed in open capillaries and are un-
corrected. UV spectra were taken in methanol solution on
U-2000 (Hitachi) UV spectrophotometer. IR spectra were
scanned in Nujol on Perkin–Elmer 842 IR spectrophotome-
ter. NMR spectra were recorded in CDCl3 using TMS as an
internal standard on 200 MHz Bruker AM-200 spectrometer
and 90 MHz Perkin Elmer spectrometer. Mass spectra were
recorded at 70 eV using a VG-70S instrument. Silica gel
(100–200 mesh) was used for column chromatography.
The columns were packed with silica gel in light-petroleum
(60–80 ꢁC) and left overnight before separation. Solvents
were dried using standard literature procedures. 2-Aroylin-
dan-1,3-dione (1) required for alkylation was prepared
according to a literature procedure.9
O
O
R2
R2
R1
O
O
R1
O
O
O
O
R2
R2
R1
O
O
R1
3.2. 2-Aroyl-2-methyl/benzylindan-1,3-dione (2):
general procedure
O
O
4 (Z)
3 (E)
R1 = H, OMe, Me ; R2 = Me, CH2Ph
A mixture of 2-aroylindan-1,3-dione (1) (0.02 mol), methyl
iodide/benzyl chloride (0.08 mol), anhydrous potassium
carbonate (11.0 g, 0.08 mol), and potassium iodide (0.5 g,
0.003 mol) was refluxed in dry acetone (200 mL) for 10 h.
The reaction mixture was cooled and the inorganic salts fil-
tered. Excess of acetone was evaporated and the reaction
mixture dispensed into water and extracted with ether
(3ꢂ50 mL). The combined ether extracts were dried over
anhydrous magnesium sulfate, filtered, and ether distilled
off. The crude product thus obtained was crystallized from
benzene–light-petroleum mixture to yield 2.
Scheme 2.
(vide experimental). Both isomers exist in the more stable
s-trans conformation rather than the s-cis conformation as
indicated by the position of the carbonyl group bands in IR
1
spectra and is well supported by H NMR spectroscopic
data. There was no substantial difference in the mass spectra
of 3 and 4. However, it was hard to explain how the signal
due to C4-H emerged at d 8.96–9.07 in (E)-3-alkylidene-
3H-isobenzofuranones as claimed by the authors.6 It was
also mentioned that E-isomers were transformed completely
to Z-isomers on treatment with concd H2SO4. In contrast, in
Compound 2a; 2.16 g, 41%; colorless crystals, mp 127–
128 ꢁC; UV: lmax¼239, 382 nm; IR: 1742, 1700,

596
S. Mor et al. / Tetrahedron 63 (2007) 594–597
1677 cmꢀ1; 1H NMR (90 MHz): d 1.73 (s, 3H, CH3), 7.20–
7.50 (m, 3H, H-30, H-40, H-50), 7.69 (dd, J¼8.0, 2.5 Hz, 2H,
H-20, H-60), 7.83–8.17 (m, 4H, H-4, H-5, H-6, H-7); Anal.
Calcd for C17H12O3: C, 77.24; H, 4.54. Found C, 77.31; H,
4.48.
3.3.1. E-3-Alkylidene-3H-isobenzofuranones (3). Com-
pound 3a; 210 mg, 42%; colorless crystals, mp 78–79 ꢁC;
1
UV: lmax¼235, 334 nm; IR: 1785, 1655 cmꢀ1; H NMR
(200 MHz): d 2.32 (s, 3H, CH3), 7.27 (dd, J¼8.6, 3.4 Hz,
1H, H-4), 7.46–7.70 (m, 5H, H-5, H-6, H-30, H-40, H-50),
7.91 (dd, J¼8.0, 3.2 Hz, 1H, H-7), 8.01 (d, J¼7.3 Hz, 2H,
H-20, H-60); MS: m/z (%) 264 (M+, 21), 187 (5), 159 (6),
131 (4), 105 (100), 103 (7), 77 (38), 76 (9), 51 (9); Anal.
Calcd for C17H12O3: C, 77.24; H, 4.54. Found C, 77.36; H,
4.45.
Compound 2b; 2.94 g, 50%; colorless crystals, mp 125–
1
126 ꢁC; IR: 1749, 1710, 1652 cmꢀ1; H NMR (90 MHz):
d 1.68 (s, 3H, CH3), 3.75 (s, 2H, OCH3), 6.75 (d,
J¼8.5 Hz, 2H, H-30, H-50), 7.65 (d, J¼8.5 Hz, 2H, H-20,
H-60), 7.77–8.13 (m, 4H, H-4, H-5, H-6, H-7); Anal. Calcd
for C18H14O4: C, 73.46; H, 4.76. Found C, 73.59; H, 4.66.
Compound 3b; 220 mg, 44%; colorless crystals, mp 119–
1
120 ꢁC; UV: lmax¼263, 295 nm; IR: 1778, 1655 cmꢀ1; H
Compound 2c; 2.55 g, 46%; colorless crystals, mp 180–
NMR (200 MHz): d 2.32 (s, 3H, CH3), 3.85 (s, 3H,
OCH3), 6.94 (d, J¼8.9 Hz, 2H, H-30, H-50), 7.20–7.30 (m,
1H, H-4), 7.30–7.55 (m, 2H, H-5, H-6), 7.84 (dd, J¼8.0,
2.1 Hz, 1H, H-7), 7.95 (d, J¼8.9 Hz, 2H, H-20, H-60); MS:
m/z (%) 294 (M+, 18), 263 (10), 136 (13), 135 (100), 107
(11), 92 (12), 77 (23); Anal. Calcd for C18H14O4: C,
73.46; H, 4.76. Found C, 73.59; H, 4.63.
181 ꢁC; UV: lmax¼215 nm; IR: 1749, 1710, 1675 cmꢀ1
;
1H NMR (90 MHz): d 1.67 (s, 3H, CH3), 2.25 (s, 3H,
CH3), 7.02 (d, J¼8.0 Hz, 2H, H-30, H-50), 7.51 (d,
J¼8.5 Hz, 2H, H-20, H-60), 7.72–8.10 (m, 4H, H-4, H-5,
H-6, H-7); Anal. Calcd for C18H14O3: C, 77.69; H, 5.03.
Found C, 77.80; H, 5.11.
Compound 2d; 3.46 g, 51%; colorless crystals, mp 140–
141 ꢁC; UV: lmax¼225, 367 nm; IR: 1741, 1701,
6.90 (s, 5H, CH2C6H5), 7.12–7.42 (m, 3H, H-30, H-40,
H-50), 7.50–7.91 (m, 6H, H-4, H-5, H-6, H-7, H-20, H-60);
Anal. Calcd for C23H16O3: C, 81.17; H, 4.70. Found C,
81.29; H, 4.61.
Compound 3c; 210 mg, 42%; colorless crystals, mp 119–
1
120 ꢁC; UV: lmax¼263, 311 nm; IR: 1780, 1650 cmꢀ1; H
1
1670 cmꢀ1; H NMR (90 MHz): d 3.70 (s, 2H, CH2C6H5),
NMR (200 MHz): d 2.32 (s, 3H, CH3), 2.44 (s, 3H, CH3),
7.25 (dd, J¼8.4, 2.1 Hz, 1H, H-4), 7.31 (d, J¼8.2 Hz, 2H,
H-30, H-50), 7.47–7.56 (m, 2H), 7.89–7.93 (m, 3H); MS:
m/z (%) 278 (M+, 11), 263 (13), 120 (12), 119 (100), 105
(12), 91 (39), 77 (13), 65 (14); Anal. Calcd for C18H14O3:
C, 77.69; H, 5.03. Found C, 77.73; H, 5.01.
Compound 2e; 3.84 g, 52%; colorless crystals, mp 152–
153 ꢁC; UV: lmax¼209, 224 nm; IR: 1741, 1703,
3.73 (s, 3H, OCH3), 6.71 (d, J¼8.5 Hz, 2H, H-30, H-50),
6.91 (s, 5H, CH2C6H5), 7.50–7.90 (m, 6H, H-4, H-5, H-6,
H-7, H-20, H-60); Anal. Calcd for C24H18O4: C, 77.83; H,
4.86. Found C, 77.65; H, 4.64.
Compound 3d; 215 mg, 43%; colorless crystals, mp 128–
1
1
1674 cmꢀ1; H NMR (90 MHz): d 3.70 (s, 2H, CH2C6H5),
129 ꢁC; UV: lmax¼248, 314 nm; IR: 1784, 1665 cmꢀ1; H
NMR (200 MHz): d 4.13 (s, 2H, CH2), 7.10–7.26 (m, 6H),
7.34–7.63 (m, 5H), 7.83 (dd, J¼7.7, 2.0 Hz, 2H, H-20,
H-60), 7.92 (dd, J¼7.6, 2.1 Hz, 1H, H-7); MS: m/z (%) 340
(M+, 58), 235 (88), 207 (13), 178 (18), 105 (100), 91 (36),
77 (62); Anal. Calcd for C23H16O3: C, 81.17; H, 4.70. Found
C, 81.15; H, 4.65.
Compound 2f; 3.89 g, 55%; colorless crystals, mp 167–
168 ꢁC; UV: lmax¼210, 313 nm; IR: 1741, 1707,
1
1674 cmꢀ1; H NMR (90 MHz): d 2.27 (s, 3H, CH3), 3.72
Compound 3e; 230 mg, 46%; colorless crystals, mp 147–
1
(s, 2H, CH2C6H5), 6.92 (s, 5H, CH2C6H5), 7.03 (d,
J¼8.0 Hz, 2H, H-30, H-50), 7.50 (d, J¼8.0 Hz, 2H, H-20,
H-60), 7.58–7.99 (m, 4H, H-4, H-5, H-6, H-7); Anal. Calcd
for C24H18O3: C, 81.35; H, 5.08. Found C, 81.57; H, 5.22.
148 ꢁC; UV: lmax¼266, 297 nm; IR: 1782, 1654 cmꢀ1; H
NMR (200 MHz): d 3.82 (s, 3H, OCH3), 4.12 (s, 2H,
CH2), 6.85 (d, J¼8.8 Hz, 2H, H-30, H-50), 7.10–7.25 (m,
6H), 7.37–7.48 (m, 2H), 7.81 (d, J¼8.8 Hz, 2H, H-20,
H-60), 7.91 (dd, J¼6.4, 2.0 Hz, 1H, H-7); MS: m/z (%)
370 (M+, 14), 339 (15), 135 (100), 107 (13), 105 (27),
104 (39), 92 (13), 91 (97), 77 (35), 65 (19); Anal. Calcd
for C24H18O4: C, 77.83; H, 4.86. Found C, 77.99; H,
4.65.
3.3. (E and Z)-3-Alkylidene-3H-isobenzofuranones
(3 and 4): general procedure
A solution of 2-aroyl-2-methyl/benzylindan-1,3-dione (2,
500 mg), in dry benzene (80 mL) was deoxygenated by bub-
bling dry nitrogen gas for 15 min. The solution was then
irradiated with a 450 W Hanovia mercury vapor lamp in
a pyrex reactor under nitrogen atmosphere. The reaction
progress was monitored by TLC (benzene–EtOAc 19:1) on
aliquots withdrawn from the reaction mixture at different
intervals of time. After 3 h of irradiation, TLC showed
complete absence of starting compound. The solvent was
distilled off and the resulting viscous photolysate was chro-
matographed over a column of silica gel (30 g, packed in
light-petroleum). The column was then eluted initially
with light-petroleum followed by benzene–light-petroleum
(1:1) affording firstly 3, followed by subsequent elution
with benzene only provided 4 in high yields.
Compound 3f; 220 mg, 44%; colorless crystals, mp 137–
1
138 ꢁC; UV: lmax¼262, 311 nm; IR: 1775, 1655 cmꢀ1; H
NMR (200 MHz): d 2.38 (s, 3H, CH3), 4.12 (s, 2H, CH2),
7.12–7.26 (m, 8H), 7.37–7.50 (m, 2H), 7.74 (d, J¼8.1 Hz,
2H, H-20, H-60), 7.91 (dd, J¼6.6, 2.1 Hz, 1H, H-7); MS:
m/z (%) 354 (M+, 29), 340 (22), 339 (78), 235 (28), 119
(100), 91 (51), 65 (13); Anal. Calcd for C24H18O3: C,
81.35; H, 5.08. Found C, 81.40; H, 5.00.
3.3.2. Z-3-Alkylidene-3H-isobenzofuranones (4). Com-
pound 4a; 220 mg, 44%; colorless crystals, mp 124–
1
125 ꢁC; UV: lmax¼234, 334 nm; IR: 1779, 1655 cmꢀ1; H
NMR (200 MHz): d 2.46 (s, 3H, CH3), 7.42–7.68 (m, 4H),

S. Mor et al. / Tetrahedron 63 (2007) 594–597
597
7.78–8.00 (m, 5H); MS: m/z (%) 264 (M+, 18), 187 (4), 159
(3), 131 (4), 105 (100), 103 (8), 77 (41), 76 (10), 51 (10);
Anal. Calcd for C17H12O3: C, 77.24; H, 4.54. Found C,
77.41; H, 4.42.
119 (100), 91 (60), 65 (18); Anal. Calcd for C24H18O3: C,
81.35; H, 5.08. Found C, 81.26; H, 5.21.
Acknowledgements
Compound 4b; 225 mg, 45%; colorless crystals, mp 161–
1
162 ꢁC; UV: lmax¼262, 290 nm; IR: 1778, 1655 cmꢀ1; H
The authors thank CSIR, New Delhi for financial support.
NMR (200 MHz): d 2.43 (s, 3H, CH3), 3.85 (s 3H, OCH3),
6.93 (d, J¼8.9 Hz, 2H, H-30, H-50), 7.62 (dd, J¼8.5,
2.5 Hz, 1H, H-4), 7.76–7.97 (m, 5H, H-5, H-6, H-7, H-20,
H-60); MS: m/z (%) 294 (M+, 18), 263 (9), 136 (11), 135
(100), 107 (8), 92 (10), 77 (17); Anal. Calcd for
C18H14O4: C, 73.46; H, 4.76. Found C, 72.53; H, 4.69.
References and notes
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50, 903–904; (b) Aidhein, I. S.; Narasimhan, N. S. Tetrahedron
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Compound 4c; 230 mg, 46%; colorless crystals, mp 128–
1
129 ꢁC; UV: lmax¼264, 312 nm; IR: 1779, 1655 cmꢀ1; H
NMR (200 MHz): d 2.42 (s, 3H, CH3), 2.44 (s, 3H, CH3),
7.26 (d, J¼8.2 Hz, 2H, H-30, H-50), 7.65 (dd, J¼8.4,
2.1 Hz, 1H, H-4), 7.77–7.86 (m, 3H, H-5, H-6, H-7), 7.97
(d, J¼8.3 Hz, 2H, H-20, H-60); MS: m/z (%) 278 (M+, 14),
263 (14), 120 (13), 119 (100), 105 (7), 91 (36), 77 (9), 65
(14); Anal. Calcd for C18H14O3: C, 77.69; H, 5.03. Found
C, 77.81; H, 5.11.
Compound 4d; 220 mg, 44%; colorless crystals, mp 147–
1
148 ꢁC; UV: lmax¼250, 314 nm; IR: 1779, 1654 cmꢀ1; H
NMR (200 MHz): d 4.30 (s, 2H, CH2), 7.17–7.42 (m,
7H), 7.50 (dd, J¼7.3, 2.1 Hz, 1H, H-40), 7.60–7.83 (m,
4H), 7.94–8.04 (m, 2H); MS: m/z (%) 340 (M+, 54), 235
(76), 207 (11), 178 (15), 105 (100), 91 (22), 77 (56);
Anal. Calcd for C23H16O3: C, 81.17; H, 4.70. Found C,
81.19; H, 4.68.
Compound 4e; 225 mg, 45%; colorless crystals, mp 126–
1
127 ꢁC; UV: lmax¼265, 292 nm; IR: 1777, 1647 cmꢀ1; H
NMR (200 MHz): d 3.83 (s, 3H, OCH3), 4.28 (s, 2H,
CH2), 6.84 (d, J¼8.8 Hz, 2H, H-30, H-50), 7.17–7.35 (m,
5H), 7.60–7.76 (m, 2H), 7.80 (d, J¼8.8 Hz, 2H, H-20,
H-60), 7.96–8.03 (m, 2H); MS: m/z (%) 370 (M+, 24), 339
(30), 135 (100), 107 (13), 105 (25), 104 (7), 92 (12), 91
(11), 77 (23), 65 (8); Anal. Calcd for C24H18O4: C, 77.83;
H, 4.86. Found C, 77.92; H, 4.68.
5. (a) Bellina, F.; Ciucci, D.; Vergamini, P.; Rossi, R. Tetrahedron
2000, 56, 2533–2545; (b) Rossi, R.; Bellina, F.; Biagetti, M.;
Catanese,A.;Mannina,L. TetrahedronLett. 2000, 41, 5281–5286.
6. Mukhopadhyay, R.; Kundu, N. G. Tetrahedron 2001, 57, 9475–
9480.
7. Lee, K. Y.; Kim, J. M.; Kim, J. N. Synlett 2003, 357–360.
8. Kapoor, M.; Dhawan, S. N.; Mor, S.; Bhatia, S. C.; Gupta, S. C.;
Hundal, M. S. Tetrahedron 2003, 59, 5027–5031.
9. (a) Dhawan, S. N.; Mor, S.; Sharma, K.; Chawla, A. D.; Gupta,
S. C. Indian J. Chem. 1994, 33B, 38–42; (b) Shapiro, L.; Geiger,
K.; Freedman, L. J. Org. Chem. 1960, 25, 1860–1865.
Compound 4f; 225 mg, 45%; colorless crystals, mp 145–
1
146 ꢁC; UV: lmax¼262, 313 nm; IR: 1775, 1655 cmꢀ1; H
NMR (200 MHz): d 2.36 (s, 3H, CH3), 4.28 (s, 2H, CH2),
7.13–7.30 (m, 7H), 7.59–7.80 (m, 4H), 7.96–8.02 (m, 2H);
MS: m/z (%) 354 (M+, 27), 340 (25), 339 (80), 235 (31),