Catalytic activity studies of aminocarbonyl group containing hoveyda-grubbs-type complexes for the syntheses of herbarumin i and stagonolide A

Article abstract of DOI:10.1055/s-0029-1219807

The catalytic activity of four aminocarbonyl group containing boomerang-type ring-closing metathesis catalysts have been studied for ten-membered lactone and compared well with the Grubbs I and II as well as the Hoveyda-Grubbs catalysts. The activity was found to be superior to the above three ring-closing metathesis catalysts and suggesting novel stereoselective total syntheses of herbarumin I and stagonolide A. Georg Thieme Verlag Stuttgart.

Full text of DOI:10.1055/s-0029-1219807

LETTER
1223
Catalytic Activity Studies of Aminocarbonyl Group Containing Hoveyda–
Grubbs-Type Complexes for the Syntheses of Herbarumin I and Stagonolide A
Catalytic
Activity
e
Studies of
t
b
he
A
minoca
r
e
bonyl
G
rou
n
p
dra K. Mohapatra,*a R. Somaiah,a M. Mallikarjuna Rao,a Fréderic Caijo,b Marc Mauduit,*b J. S. Yadav*a
a
Organic Chemistry Division-I, Indian Institute of Chemical Technology (CSIR), Uppal Road, Hyderabad 500 007, India
Fax +91(40)27160512; E-mail: mohapatra@iict.res.in
b
Wcat SYSTEM®, Ecole Nationale Supérieure de Chimie de Rennes, Av. Du Général Leclerc, 35700 Rennes, France
Received 2 March 2010
four well defined, air-stable ‘boomerang’-type metathesis
catalysts10 compared well with the Grubbs first- and sec-
ond-generation and Hoveyda–Grubbs catalysts for decan-
olide suggesting a novel route towards the syntheses of
Abstract: The catalytic activity of four aminocarbonyl group con-
taining ‘boomerang’-type ring-closing metathesis catalysts have
been studied for ten-membered lactone and compared well with the
Grubbs I and II as well as the Hoveyda–Grubbs catalysts. The activ-
ity was found to be superior to the above three ring-closing metathe- herbarumin I and stagonolide A. Recently, the first stereo-
sis catalysts and suggesting novel stereoselective total syntheses of
selective total synthesis of stagonolide A has been report-
ed.11
herbarumin I and stagonolide A.
Key words: decanolides, stagonolides, herbarumin I, Wittig reac-
tion, ring-closing metathesis
O
OH
OH
O
O
OH
The generic name decanolides encompasses a relatively
small group of naturally occurring ten-membered lactones
of polyketides origin isolated in most cases from various
species of fungi.1 Stagonospora cirsii is a pathogen of
Cirsium arvense and demonstrated development of a
mycoherbicide. A new decanolide, named stagonolide A,
was isolated and characterized as (8R,9R)-8-hydroxy-7-
oxo-9-propyl-5-nonen-9-olide by spectral and analytical
methods.2 Stagonolide A was shown to be a nonhost-
specific but selective phytotoxin. Stagonolide A is struc-
turally related to several known fungal ten-membered lac-
tones, for instance, putaminoxins3 isolated from Phoma
putaminum, a pathogen of Erigeron annuus (Asteraceae),
pinolidoxins4 isolated from Ascochyta pinodes, a patho-
gen of peas (Fabaceae), lethaloxins5 and herbarumins iso-
lated from Phoma herbarum, a pathogen of Zea mays
(Poaceae).6 Among them, herbarumin I7 is the most relat-
ed to stagonolide A (Figure 1). Surprisingly, among in-
vestigated natural phytotoxic ten-membered lactones,
there are no structures with a ketonic carbonyl group in
the lactone ring at C7, similar to stagonolide.8 These nat-
urally occurring ten-membered lactones, isolated from
fungal metabolites, commonly known as decanolides,
have attracted considerable attention from synthetic or-
ganic chemists as well as bioorganic chemists because of
their interesting structures and various biological activity
like plant-growth inhibition, antifeedant, antifungal, and
antibacterial activities.
O
O
stagonolide A (1)
herbarumin I (2)
OH
OH
OH
OH
O
O
O
O
O
O
O
O
pinolidoxin (3)
lethaloxin (4)
Figure 1 Structures of stagonolide A, herbarumin I, pinolidoxin,
and lethaloxin
O
6
4
OH
7
3
5
O
OH
1
O
9
2
8
OH
O
O
stagonolide A (1)
herbarumin I (2)
OH
O
OH
7
+
O
OBn
OH OTBS
O
The construction of lactones through the formation of a
C–C bond and particularly by ring-closing metathesis
reaction (RCM)9 is a promising tool for decanolides. In
this communication, we found that the catalytic activity of
OBn
5
6
D-glucose
SYNLETT 2010, No. 8, pp 1223–1226
x
x.
x
x.
2
0
1
0
Advanced online publication: 09.04.2010
DOI: 10.1055/s-0029-1219807; Art ID: G05410ST
Scheme 1 Retrosynthetic analysis of herbarumin I and stagonolide A
© Georg Thieme Verlag Stuttgart · New York

1224
D. K. Mohapatra et al.
LETTER
According to our retrosynthetic analysis (Scheme 1), the CH2Cl2 with high dilution and under reflux conditions
construction of the ten-membered lactones 1 and 2 would gave the desired lactone 1217 in 45% yield as the only
arise from the formation of C5–C6 olefin linkage from product (E-isomer) after 48 hours with 42% recovery of
bisalkene 5 which in turn would be prepared via the ester- the starting material, whereas the second-generation cata-
ification of alcohol 6 and acid 7. The synthesis of alcohol lyst (10 mol%) afforded the required product in 72% yield
6 could be obtained from D-glucose in a concise and high- in 12 hours. When the Hoveyda–Grubbs catalyst (10
yielding manner.
mol%) was used for the same reaction, lactone 12 ob-
tained in 75% yield as the only product. Next, the scope of
the metathesis transformation catalyzed by the amino car-
bonyl group containing Hoveyda–Grubbs-type (‘boomer-
ang’-type catalysts) complexes was investigated. The
‘boomerang“-type catalysts (Scheme 2) were found to be
extremely competent because only 1 mol% catalyst and a
reaction time of 1 hours was required to complete the
RCM reaction of 5 at room temperature to afford the de-
sired compound 12 in 84–95% yield (Table 1) as the only
product.18
The synthesis of the alcohol fragment 6 began with a
known intermediate 8 which in turn was obtained from D-
glucose.12 Deprotection of the 1,2-O-isopropylidene
group of 8 with 20% AcOH in H2O and a catalytic amount
of H2SO4 afforded the lactol 9 in 88% yield, which after
workup was subjected to one-carbon Wittig
homologation13 with in situ generated methylenetriphe-
nylphosphorane to afford the olefinic intermediate 1014 in
84% yield. Selective protection of the allylic hydroxyl
group as its TBDMS ether and esterification with 5-hex-
enoic acid under EDCI and DMAP conditions at room After having the desired compound 12 in good yield and
temperature gave the intermediate 1115 in 85% yield over selectivity, the next task was to deprotect the benzyl group
two steps (Scheme 2). RCM reaction on substrate 11 did under excess TiCl419 (10 equiv) and CH2Cl2 at room tem-
not work with the above metathesis catalysts under differ- perature to afford the herbarumin I (2)20 in 89% yield
ent reaction conditions. Deprotection of the TBS ether whose spectral and analytical data were in good agree-
with HF–pyridine complex afforded the desired RCM ment with the reported values (Scheme 3).6a,7b Finally, se-
precursor 5 in 92% yield.16
lective oxidation of the allylic hydroxyl group with MnO2
in CH2Cl2 gave the stagonolide A (1)21,11 in 84% yield.
The spectral and analytical data were in an excellent ac-
cord with the natural product which reconfirmed the abso-
lute configuration to be (8R,9R).2,11
The RCM reaction was then investigated using Grubbs
first- and second-generation catalysts. The reaction of 5
with Grubbs first-generation catalyst (20 mol%) in
20% AcOH
O
TBSCl
imidazole, CH2Cl2
MePh3PI
n-BuLi, THF
OH
OH
O
cat. H2SO4
ref. 12
D-glucose
OH
O
50 °C, 12 h
88%
0 °C to r.t., 6 h
94%
0 °C to r.t., 8 h
84%
BnO
BnO
OBn
O
OH
8
9
10
cat.
OH
OTBS
7, EDCI
DMAP, CH2Cl2
HF–py
THF
OH
OH
OTBS
CH2Cl2
O
reflux to r.t., 1–48 h
45–95%
O
O
0 °C to r.t., 3 h
92%
0 °C to r.t., 12 h
90%
OBn
OBn
OBn
OBn
O
O
O
6
11
5
12
PCy3
Cl
Cl
N
N
N
N
N
N
Ru
PCy3
G-I
Mes
Mes
Ph
Cl
Cl
Cl
Cl
Ru
O
Ru
Ru
O
Cl
Ph
Cl
PCy3
O
G-II
Ot-Bu
N
H
HG
M73SIPr
N
N
N
N
N
N
Cl
Cl
Cl
Ru
O
Ru
O
Ru
O
Cl
Cl
Cl
O
O
O
Ot-Bu
CF3
CF3
N
N
N
H
H
H
M73SIMes
M71SIMes
M71SIPr
Scheme 2 Catalytic activity studies of ‘boomerang’ catalysts
Synlett 2010, No. 8, 1223–1226 © Thieme Stuttgart · New York

LETTER
Catalytic Activity Studies of the Aminocarbonyl Group
1225
References and Notes
Table 1 Results of RCM Reaction
(1) (a) Dräger, G.; Kirschning, A.; Thiericke, R.; Zerlin, M. Nat.
Prod. Rep. 1996, 13, 365. (b) Ferraz, H. M. C.; Bombonato,
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(c) Evidente, A.; Capasso, R.; Andolfi, A.; Vurro, M.;
Zonno, M. C. Phytochemistry 1998, 48, 941.
Entry
Catalyst
G-I
Conditions
Time (h) Yield (%)a
1
2
3
4
5
6
7
CH2Cl2, reflux
CH2Cl2, reflux
CH2Cl2, reflux
CH2Cl2, r.t.
CH2Cl2, r.t.
CH2Cl2, r.t.
CH2Cl2, r.t.
48
12
12
1
45
72
75
84
90
92
95
G-II
HG
M71SIMes
M73SIMes
M71SIPr
M73SIPr
1
1
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Bottalico, A. Phytochemistry 1993, 34, 999. (b) Evidente,
A.; Capasso, R.; Bouzeid, M. A.; Lanzetta, R.; Vurro, M.;
Bottalico, A. J. Nat. Prod. 1993, 56, 1937.
1
a Isolated yield and only E-isomer.
(5) Arnone, A.; Assante, G.; Montorsi, M.; Nasini, G.; Ragg, E.
Gazz. Chim. Ital. 1993, 123, 71.
(6) (a) Rivero-Cruz, J. F.; Macias, M.; Gerda-Garcia-Rojas, C.
M.; Mata, R. Tetrahedron 2000, 56, 5337. (b) Rivero-Cruz,
J. F.; Macias, M.; Gerda-Garcia-Rojas, C. M.; Mata, R.
J. Nat. Prod. 2003, 66, 511.
excess TiCl4
CH2Cl2
OH
OH
OH
O
0 °C to r.t., 30 min
89%
O
OBn
O
O
(7) (a) Fürstner, A.; Radkowski, K. Chem. Commun. 2001, 671.
(b) Fürstner, A.; Radkowski, K.; Wirtz, C.; Goddard, R.;
Lehmann, W. C.; Mynott, R. J. Am. Chem. Soc. 2002, 124,
7061. (c) Sabino, A. A.; Pilli, R. A. Tetrahedron Lett. 2002,
43, 2819. (d) Diez, E.; Dixon, D. J.; Ley, S. V.; Polara, A.;
Rodriguez, F. Helv. Chim. Acta 2003, 86, 3717. (e) Gurjar,
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Karmakar, S.; Mohapatra, D. K. ARKIVOC 2005, (iii), 237.
(h) Salaskar, A.; Sharma, A.; Chattopadhyay, S.
herbarumin I (2)
12
CH2Cl2
12 h, 84%
MnO2
r.t.
O
O
OH
O
Tetrahedron: Asymmetry 2006, 17, 325. (i) Boruwa, J.;
Gogoi, N.; Barua, N. C. Org. Biomol. Chem. 2006, 4, 3521.
(j) Gupta, P.; Kumar, P. Tetrahedron: Asymmetry 2007, 18,
1688. (k) Nagaiah, K.; Sreenu, D.; Rao, R. S.; Yadav, J. S.
Tetrahedron Lett. 2007, 48, 7173. (l) Yadav, J. S.; Kumar,
V. N.; Rao, R. S.; Srihari, P. Synthesis 2008, 1938.
(m) Yadav, J. S.; Ather, H.; Gayathri, K. U.; Rao, N. V.;
Prasad, A. R. Synthesis 2008, 3945. (n) Selvam, J. J. P.;
Rajesh, K.; Suresh, V.; Babu, D. C.; Venkateswarlu, Y.
Tetrahedron: Asymmetry 2009, 20, 1115. (o) Kamal, A.;
Venkata Reddy, P.; Prabhakar, S. Tetrahedron: Asymmetry
2009, 20, 1120.
stagonolide A (1)
Scheme 3 Syntheses of herbarumin I and stagonolide A
In conclusion, we have shown that well-defined, air-
stable, four aminocarbonyl group containing Hoveyda–
Grubbs-type complexes are more effective for ten-mem-
bered lactones compared to Grubbs and Hoveyda–Grubbs
catalysts and en route achieved a convergent synthesis of
pharmacologically active herbarumin I and stagonolide A
starting from commercially available D-glucose. All these
new air-stable catalysts are under investigation for RCM
reaction for different substrates leading to lactones of dif-
ferent ring sizes and substituents at the double bond.
(8) (a) Evidente, A.; Cimmino, A.; Berestetskiy, A.; Mitina, G.;
Andolfi, A.; Motta, A. J. Nat. Prod. 2008, 71, 31.
(b) Evidente, A.; Cimmino, A.; Berestetskiy, A.; Andolfi,
A.; Motta, A. J. Nat. Prod. 2008, 71, 1897.
(9) (a) Grubbs, R. H.; Chang, S. Tetrahedron 1998, 54, 4413.
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371. (c) Fürstner, A. Angew. Chem. Int. Ed. 2000, 39, 3012.
(d) Maier, M. E. Angew. Chem. Int. Ed. 2000, 39, 2073.
(e) Nevalainen, M.; Koskinen, A. M. P. Angew. Chem. Int.
Ed. 2001, 40, 4060. (f) Trnka, T. M.; Grubbs, R. H. Acc.
Chem. Res. 2001, 34, 18. (g) Prunet, J. Angew. Chem. Int.
Ed. 2003, 42, 2826. (h) Love, J. A. In Handbook of
Metathesis; Grubbs, R. H., Ed.; Wiley-VCH: Weinheim,
2003, 296–322. (i) Grubbs, R. H. Tetrahedron 2004, 60,
7117. (j) Deiters, A.; Martin, S. F. Chem. Rev. 2004, 104,
2199. (k) Gradillas, A.; Pérez-Castells, J. Angew. Chem. Int.
Ed. 2006, 45, 6086.
Supporting Information for this article is available online at
http://www.thieme-connect.com/ejournals/toc/synlett.
Acknowledgment
RS and MMR thank the Council of Scientific & Industrial Research
(CSIR), New Delhi, India, for the financial assistance in the form of
fellowships. DKM thanks to CSIR for a research grant (INSA
Young Scientist Award). MM thanks to EUMET for the financial
support through the seventh framework program through grant (CP-
FP 211468-2 EUMET).
Synlett 2010, No. 8, 1223–1226 © Thieme Stuttgart · New York

1226
D. K. Mohapatra et al.
LETTER
(10) (a) Rix, D.; Caijo, F.; Laurent, I.; Gulajski, L.; Grela, K.;
Mauduit, M. Chem. Commun. 2007, 3771. (b) Rix, D.;
Caijo, F.; Laurent, I.; Boeda, F.; Clavier, H.; Nolan, S. P.;
Mauduit, M. J. Org. Chem. 2008, 73, 4225. (c) Clavier, H.;
Caijo, F.; Borré, E.; Rix, D.; Boeda, F.; Nolan, S. P.;
Mauduit, M. Eur. J. Org. Chem. 2009, 4254.
(11) Srihari, P.; Kumaraswamy, B.; Rao, G. M.; Yadav, J. S.
Tetrahedron: Asymmetry 2010, 21, 106.
(12) Kirihata, M.; Ohe, M.; Ichimoto, I.; Ueda, H. Biosci.
(300 MHz, CDCl3): d = 7.40–7.30 (m, 5 H), 5.68–5.57 (m, 1
H), 5.50 (dd, J = 15.7, 1.1 Hz, 1 H), 5.21 (dt, J = 9.5, 1.1 Hz,
1 H), 4.73–4.53 (m, 3 H), 3.37 (dd, J = 9.6, 1.9 Hz, 1 H),
2.34–2.27 (m, 2 H), 2.03–1.78 (m, 4 H), 1.49 (m, 1 H), 1.36–
1.22 (m, 4 H), 0.89 (t, J = 7.4 Hz, 3 H). 13C NMR (75 MHz,
CDCl3): d = 175.5, 137.3, 133.1, 130.3, 128.5, 128.0, 124.6,
80.9, 72.3, 68.8, 68.8, 34.5, 33.6, 33.5, 24.5, 17.8, 13.9.
HRMS: m/z calcd for C19H26O4Na: 341.1728; found:
341.1722.
Biotech. Biochem. 1992, 56, 1825.
(13) Freeman, F.; Robarge, K. D. Carbohydr. Res. 1986, 154,
270.
(18) General Procedure for the Metathesis Reaction
To a stirred solution of diene (1.0 mmol) in freshly prepared
dry CH2Cl2 (200 mL) at r.t. was added the metathesis
catalyst (0.01 mmol) under argon. The progress of the
reaction was monitored by TLC. After completion of the
reaction, solvent was removed under reduced pressure. The
crude product was purified by flash column chromatography
(EtOAc–hexane = 1:6) to afford the E-isomer as the sole
product.
(14) Analytical and Spectral Data of 10
[a]D25 +7.6 (c 1.1, CHCl3). IR (neat): 3455, 2924, 2852,
2097, 1461 cm–1. 1H NMR (300 MHz, CDCl3): d = 7.43–
7.19 (m, 5 H), 6.05 (m, 1 H), 5.34 (dd, J = 17.3, 1.5 Hz, 1 H),
5.18 (dd, J = 10.6, 1.5 Hz, 1 H), 4.60 (ABq, J = 13.6, 11.3
Hz, 2 H), 4.31 (t, J = 5.3 Hz, 1 H), 3.74 (m, 1 H), 3.25 (t,
J = 6.04 Hz, 1 H), 2.90 (br s, 1 H), 2.59 (br s, 1 H), 1.69–1.24
(m, 4 H), 0.92 (t, J = 6.8 Hz, 3 H). 13C NMR (75 MHz,
CDCl3): d = 137.7, 137.9, 137.7, 128.4, 127.8, 128.1, 116.1,
84.2, 73.9, 73.7, 72.6, 35.3, 18.8, 14.0. HRMS: m/z calcd for
C15H22O3Na: 273.1466; found: 273.1472.
(19) (a) Corey, E. J.; Gras, J. L.; Ulrisch, P. Tetrahedron Lett.
1976, 17, 809. (b) Bhatt, M. V.; Kulkarni, S. V. Synthesis
1983, 249.
(20) Analytical and Spectral Data of 2
[a]D25 +10.6 (c 1.0, EtOH); lit.:7b [a]D20 +10.8 (c 0.51,
EtOH). 1H NMR (300 MHz, CDCl3): d = 5.61 (d, J = 15.9
Hz, 1 H), 5.49 (m, 1 H), 4.95 (td, J = 9.4, 2.2 Hz, 1 H), 4.42
(br s, 1 H), 3.51 (d, J = 9.8 Hz, 1 H), 2.76 (br s, 1 H), 2.45–
2.25 (m, 2 H), 2.06–1.81 (m, 4 H), 1.56 (m, 1 H), 1.43–1.18
(m, 3 H), 0.91 (t, J = 7.3 Hz, 3 H). 13C NMR (75 MHz,
CDCl3): d = 176.3, 130.7, 124.6, 73.6, 73.3, 70.1, 34.4, 33.6,
33.3, 24.6, 17.9, 13.8. IR (neat): nmax = 3455, 3038, 2955,
2920, 2867, 1711, 1639, 1219 cm–1. HRMS: m/z calcd for
C12H20O4Na: 251.1259; found: 251.1264.
(15) Analytical and Spectral Data of 11
[a]D25 +27.0 (c 0.7, CHCl3). IR (neat): nmax = 3398, 2963,
2925, 2855, 1723, 1711, 1639, 1461, 1129 cm–1. 1H NMR
(300 MHz, CDCl3): d = 7.38–7.23 (m, 5 H), 6.02–5.68 (m,
2 H), 5.29–5.12 (m, 2 H), 5.07–4.95 (m, 2 H), 4.66 (ABq,
J = 17.2, 11.5 Hz, 2 H), 4.21–4.06 (m, 2 H), 3.50 (t, J = 4.7
Hz, 1 H), 2.33–2.24 (m, 2 H), 2.14–2.06 (dd, J = 7.4, 6.9 Hz,
2 H), 1.78–1.63 (m, 4 H), 1.40–1.22 (m, 2 H), 0.96–0.84 (m,
12 H), 0.07 (s, 3 H), 0.04 (s, 3 H). 13C NMR (75 MHz,
CDCl3): d = 172.7, 138.5, 138.1, 137.6, 128.2, 127.8, 127.5,
116.5, 115.3, 83.9, 74.6, 74.0, 73.7, 34.9, 33.7, 33.1, 31.5,
25.8, 24.1, 18.7, 14.0, –4.2, –5.0. HRMS: m/z calcd for
C27H44O4NaSi: 483.2906; found: 483.2914.
(21) Analytical and Spectral Data of 1
Mp 71–72 °C; [a]D25 –59.2 (c 0.5, EtOH). 1H NMR (300
MHz, CDCl3): d = 6.42 (d, J = 16.0 Hz, 1 H), 6.32 (m, 1 H),
4.65 (dt, J = 9.5, 2.4 Hz, 1 H), 4.05 (dd, J = 9.5, 6.2 Hz, 1 H),
3.57 (d, J = 6.2 Hz, 1 H), 2.57–2.41 (m, 2 H), 2.20–1.90 (m,
6 H), 1.43–1.18 (m, 3 H), 0.93 (t, J = 7.2 Hz, 3 H). 13C NMR
(75 MHz, CDCl3): d = 199.5, 174.2, 143.1, 131.9, 76.5, 74.4,
34.2, 34.0, 33.5, 24.9, 18.0, 13.7. IR (neat): nmax = 3468,
2925, 1740, 1700, 1638, 1219 cm–1. HRMS: m/z calcd for
C12H19O4: 227.1278; found: 227.1274.
(16) (a) Nicolaou, K. C.; Seitz, S. P.; Pavia, M. R.; Petasis, N. A.
J. Org. Chem. 1979, 44, 4011. (b) Hayward, C. M.;
Yohannes, D.; Danishefsky, S. J. J. Am. Chem. Soc. 1993,
115, 9345.
(17) Analytical and Spectral Data of 12
[a]D25 +18.2 (c 1.0, CHCl3). IR (film): nmax = 4272, 3801,
3471, 2954, 1722, 1641, 1371, 1217, 1091 cm–1. 1H NMR
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