Synthesis of pyrazolidinone analogs of β-lactam antibiotics

Article abstract of DOI:10.1016/S0040-4020(01)01195-4

5-Substituted pyrazolidin-3-ones, easily available by the conjugate addition-rearrangement of hydrazine to the 2,3-unsaturated sugar 1,5-lactones, react with 2 Ms equiv. of dimethyl acetylenedicarboxylate (DMAD) to give corresponding 2,3-dihydro-5,6,7-trimethoxycarbonyl-5-methoxycarbonylmethyl-1-oxo-1H,5H- pyrazolo[1,2-a]pyrazoles. Reaction proceeds via addition of the amine group of pyrazolidin-3-one to DMAD, rearrangement of the adduct leading to the azomethine-imine ylide followed by the 1,3-dipolar cycloaddition of second DMAD molecule. The cycloaddition product may undergo intramolecular addition of hydroxy group from the polyol side chain to the double bond to give tricyclic compounds. Reaction of pyrazolidin-3-one with DMAD is accompanied by the formation of several by-products, identification of which made possible to propose reaction pathway.

Full text of DOI:10.1016/S0040-4020(01)01195-4

TETRAHEDRON
Pergamon
Tetrahedron 58 62002) 1199±1212
Synthesis of pyrazolidinone analogs of b-lactam antibiotics
a
Irma Pan®l, Zo®a Urbanczyk-Lipkowska, Kinga Suwinska, Jolanta Solecka
a
b
c
Â
Â
a,p
andMarek Chmielewski
aInstitute of Organic Chemistry, Polish Academy of Sciences, 01-224 Warsaw, Poland
bInstitute of Physical Chemistry, Polish Academy of Sciences, 01-224 Warsaw, Poland
cNational Institute of Hygiene, 00-791 Warsaw, Poland
Received3 September 2001; revised30 October 2001; accepted29 November 2001
AbstractÐ5-Substituted pyrazolidin-3-ones, easily available by the conjugate addition±rearrangement of hydrazine to the 2,3-unsaturated
sugar 1,5-lactones, react with 2 Ms equiv. of dimethyl acetylenedicarboxylate 6DMAD) to give corresponding 2,3-dihydro-5,6,7-trimethoxy-
carbonyl-5-methoxycarbonylmethyl-1-oxo-1H,5H-pyrazolo[1,2-a]pyrazoles. Reaction proceeds via addition of the amine group of pyra-
zolidin-3-one to DMAD, rearrangement of the adduct leading to the azomethine-imine ylide followed by the 1,3-dipolar cycloaddition of
second DMAD molecule. The cycloaddition product may undergo intramolecular addition of hydroxy group from the polyol side chain to the
double bond to give tricyclic compounds. Reaction of pyrazolidin-3-one with DMAD is accompanied by the formation of several
by-products, identi®cation of which made possible to propose reaction pathway. q 2002 Elsevier Science Ltd. All rights reserved.
1. Introduction
the a,b-unsaturatedsugar d-lactones. We establishedthat
the nucleophile approaches lactone molecule anti to the
terminal C-6 carbon atom 6Scheme 1) which leads to the
formation of Michael adducts 3.
The continuing andwidespreademergence of bacterial anti-
biotic resistance necessitates the search for the new active
entities. The reports of novel classes of non-b-lactam
analogs of penicillin andcephalosporin have generated
high levels of interest in many laboratories.1,2 Considerable
attention has been directed at the pyrazolo-pyrazolone
derivatives 1, since in some cases they exhibit high anti-
bacterial activity.2
Michael adducts 3 rearrange immediately to the correspond-
ing isoxazolidin-5-ones 4 6for XˆO)3 or to the pyrazolidin-
3-ones 4 6for XˆNH).4 The ability to control the absolute
con®guration at C-3 or C-5 andthe presence of polyol side
chain at C-5 or C-3, respectively, has promptedus to investi-
gate the possibility of transformation of compounds 4 into
the non-b-lactam analogs of cephams and/or penams 5±7
6Chart 1).
Recently, several derivatives of 5 were synthesizedand
evaluatedfor the antibacterial activity. However, these
5
compounds have not shown promising antibacterial
properties. Moreover, the most interesting compound 5
6with R3ˆCO2n-Bu) exhibitedlow stability, particularly in
the presence of base.5
We have reported the highly stereoselective conjugate addi-
tion±rearrangement of hydroxylamines3 andhydrazines 4 to
Scheme 1. R1ˆBn, Ac, TBS; R2ˆH, OBn, OAc, OTBS; R3ˆH, Bn; XˆO, NH.
Keywords: pyrazolidinone; 1,3-dipolar cycloaddition; azomethine-imine ylide.
Corresponding author. Tel.: 148-22-6323789; fax: 148-22-6326681; e-mail: chmiel@icho.edu.pl
p
0040±4020/02/$ - see front matter q 2002 Elsevier Science Ltd. All rights reserved.
PII: S0040-4020601)01195-4

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I. Pan®l et al. / Tetrahedron 58 +2002) 1199±1212
Chart 1. R1ˆH, Bn, Ac, TBS; R2ˆCH3, CH2OR1; R3ˆCH3, CH2OBn, CO2n-Bu; R4ˆH. Me, Bn; R5, R6ˆH, CH3, CO2n-Bu; EWGˆelectron withdrawing
group.
It remainedof interest, however, to synthesize andevaluate
derivatives of pyrazolo-oxazine and/or pyrazolo-
earlier,5 their pyrazolidine analogs 21, 23 and 25 did not
show inhibitory activity towards dd-carboxypeptidase
6Chart 2).
6
pyrazolone 7. The structure of the latter, incidentally, is
closely relatedto that of 1. We expect that compounds
such as 6 and/or 7 shouldbe more stable than their
isoxazolidinone congeners. Considering that intermediary
lactones 2 are easily available from either d-glucose or
l-rhamnose it was thought that the compounds with general
structures 6 and 7 couldpotentially be obtainedin both
enantiomeric forms.
Bipyrazolidine antibiotics
1
were obtainedfrom
pyrazolidin-3-ones 26 by a two-step reaction sequence
involving formation of an azomethine-imine ylide 27
which subsequently reactedin situ with the acetylene
derivative 6Scheme 3).2,7,8
A similar reaction sequence carriedout with pyrazolidin-3-
one 18, using n-butyl glyoxylate anddimethyl acetylene-
dicarboxylate 6DMAD) in boiling toluene, and in the
presence of acidcatalyst, ledto the formation of three
products: a pair of diastereomers 28 and 29 anda cyclic
aminal 30 in a ratio 1:3:1.5, respectively. This mixture
was subsequently separated into the individual components.
The structure andcon®guration of 28 and 29 was assigned
with the help of NOE experiments which showeda spin±
spin interaction between protons in the vicinity of amine
nitrogen atom, H-2 andH-8 6Scheme 4). Consequently,
the 6S)-con®guration was assignedto the C-2 proton. In
the case of compound 28, the value of vicinal coupling
constant 6J2,3ˆ8.1 Hz) between protons of pyrazolidine
ring was indicative of their cis arrangement, whereas the
respective coupling constant value 6J2,3ˆ13.5 Hz) found
for compound 29 indicated the trans con®guration.
2. Results and discussion
For the present study we selected the 5-substituted
pyrazolidin-3-ones 13±20 which were obtainedidrectly
from the corresponding lactones 8±12 in reaction with
either hydrazine or N-methylhydrazine, according to the
known methodology 6Scheme 2).4,6 We anticipatedthat
pyrazolidin-3-ones 13±20 wouldbe more stable as the
isoxazolidin-5-ones discussed earlier.
Pyrazolidin-3-ones with 2-N-methyl or 2-N-benzyl sub-
stituents 6compounds 13, 14 and 17) were reactedwith
butyl glyoxylate to give corresponding acetals 21±24.
Structure andcon®guration of the acetal 21 was established
by the X-ray crystallography 6Fig. 1), whereas structures of
corresponding compounds 23 and 24 were assignedon the
basis of similarity of their respective 1H NMR spectral data
with that recorded for compound 21. Compound 21 was
accompaniedby a small amount of its C-2 epimer 22. As
was the case with isoxazolidino-oxazines 5 investigated
Stereochemistry of the cyclic aminal 30 andits desilylated
derivative 31 was assignedby analogy to compound 21. It
can be expectedthat an effective formation of the
bipyrazolidines from pyrazolidin-3-ones 13±20 having a
Scheme 2.

I. Pan®l et al. / Tetrahedron 58 +2002) 1199±1212
1201
nitrogen). The double N- and O-protection was exempli®ed
by the reaction of 17 with TBSCl in DMF, which yielded 32
6Scheme 5).
Silylation of 16 in acetonitrile followedby the reaction of
resulting ether 34 with acetone andthen with DMAD
afforded expected compound 36 6Scheme 5).
In the course of the reaction of pyrazolidin-3-ones 13±20
with carbonyl compounds and DMAD, we have noticed
occasional formation of products resulting from addition
of two molecules of DMAD to one molecule of pyrazoli-
din-3-one. It should be noted that reactions of DMAD with
primary or secondary amines, as well as with variety of
heterocyclic compounds, have been reviewed in the
past.9±11 It has been shown that base- or acid-catalyzed
additions, self condensations and rearrangements lead to
formation of complex mixtures of products which, as a
rule, require careful chromatographic separation prior to
their identi®cation.9±11
Reaction of compound 34 with 2.2 M equiv. of DMAD
in acetonitrile at room temperature gave adduct 37 accom-
paniedby the by-product 38 which was characterizedas
respective acetate 39; the con®guration at the double bond
in 38 and 39 was not assigned6Scheme 6).
Attemptedformation of a bipyrazolidine ring system by the
reaction of pyrazolidin-3-ones lacking protection of the
hydroxy group in the polyol side chain with DMAD at
room temperature ledto the mixture of unstable products.
These requiredacetylation prior to the chromatographic
puri®cation andisolation of by-products. Thus, pyrazoli-
dinone 16 treatedwith DMAD at room temperature gave
a mixture of products which were characterized after
acetylation as 40±42 6Scheme 7).
In contrast, treatment of compound 16 with DMAD in boil-
ing benzene in the presence of p-TsOH ledto formation of
mixture of two tricyclic diastereomers 43 and 44 in a ratio
4:1, respectively 6Scheme 8). Compounds 43 and 44 have
similar values of vicinal coupling constants between H-6, 7,
8 and9 protons in their 1H NMR spectra, which strongly
suggest presence of the same tricyclic skeleton in both
products. The assignment of structure and con®guration of
both reaction products was based on the assumption that
the con®guration at C-2 is the same as it is foundin
compound 40 at C-6. For the more abundant product 43,
the methoxycarbonyl group at C-3 was assignedthe exo-
con®guration.
In the case of compound 20, which has the enantiomeric
relation to 16, the reaction with DMAD proceeded in
analogous manner. Two isolatedbipyrazoliidne stereo-
isomers 45 and 46 were obtainedin ratio 10:1, respectively.
The structure andcon®guration of the more abundant 45
was assignedby analogy with 40. Diastereomers 45 and
46 were accompaniedby a minute amount of the crystalline
azomethine-imine ylide 47. Its structure andabsolute
con®guration was establishedby the X-ray crystallography
6Fig. 1) 6Chart 3).
Figure 1. X-Ray structures of cephams 21, 47, and 54 with crystallographic
numbering scheme.
free hydroxy group in the side chain would require prior
hydroxy group protection, otherwise N,O-acetals can be
formed. The selective O-silylation can be achievedby
carrying out the reaction in acetonitrile solution 6if the
DMF solution is usedthe silylation of hydroxyl group is
accompaniedby the simultaneous formylation of the N-1
As a result of re¯ux in benzene in the presence of p-TsOH,

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I. Pan®l et al. / Tetrahedron 58 +2002) 1199±1212
Chart 2.
Scheme 3.
Scheme 4. NOE's values between H-2 andH-8 protons are shown on structures of 28 and 29.
Scheme 5.

I. Pan®l et al. / Tetrahedron 58 +2002) 1199±1212
1203
Scheme 6.
Scheme 7.
Scheme 8.
Chart 3.
Scheme 9.

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I. Pan®l et al. / Tetrahedron 58 +2002) 1199±1212
compound 20 gave two tricyclic compounds 50 and 51 in a
ratio of about 3.4:1, respectively 6Scheme 9).
were able to establish the stereochemistry of 54 6Fig. 1), 56,
62, and 64 6Fig. 2) by the X-ray structure analysis. It should
be notedthat the unequivocal structure assignment of these
intermediates provided a sound base for the proposed path-
way of the reaction between the pyrazolidinones having
polyol side chain and DMAD.
The structure andcon®guration assignments of compounds
37, 40, 43±46, 50 and 51 are basedon the assumption that
the con®guration in the vicinity of the NvC double bond in
the isolatedylide 47 represents the more stable arrangement.
Furthermore, we assumedthat this preferredarrangement
controls the stereochemical course of all reactions between
pyrazolidin-3-ones and DMAD. Consequently, the subse-
quent 61,3)-dipolar cycloaddition involving the ylide and
the next molecule of DMAD shouldproceed anti to the
polyol side chain. Such an assumption is strongly supported
by the X-ray analysis of crystalline compound 54 6Fig. 1).
Condensation of pyrazolidin-2-ones or acyl hydrazines with
aldehydes or ketones is a well-known process that produces
azomethine-imines that are active in the 1,3-dipolar
cycloadditions.7,8,12±15 However, the formation of analogous
azomethine-imines during the reaction of pyrazolidin-3-
ones with acetylene dicarboxylate esters has not been
reportedpreviously.
The reaction of pyrazolidin-3-one 19 with DMAD proceeds
slowly, but analogously to the reactions reportedabove. The
complicatedmixture of products 52, 53, 55, 57, 59, 61, 63
and 64 can be, however, separated into the individual
components. Acetylation leading to the corresponding acet-
ates 54, 56, 58, 60 and 62 simpli®edstructural assignments
6Chart 4).
The results presentedabove allowedus to propose the
general pathway for the reaction between pyrazolidin-3-
one and DMAD. The diagram provided below 6Scheme 3)
uses pyrazolidin-3-one 20 as an example. The ®rst molecule
of DMAD can add to the N-1 6amine) or to N-2 6amide)
nitrogen atom of pyrazolidin-3-one 20 to produce diesters
65 and/or 66, respectively. Addition to the more nucleo-
philic N-1 nitrogen atom is signi®cantly preferred.16 Adduct
65 can rearrange to the ylide 47. The E-con®guration of the
CvN double bond is preferred. The second molecule of
DMAD approaches ylide 47 anti to the polyol side chain
to generate preferentially the bis-pyrazolidine skeleton 45.
The tetraester 67 might be formeddirectly from compound
After prolongedre¯ux in toluene in the presence of p-TsOH,
compound 63 gave crystalline tricyclic compound 64.
Fortuitously, a number of crystalline acetates were obtained
in some of the reactions discussed earlier. As a result we
Chart 4.

I. Pan®l et al. / Tetrahedron 58 +2002) 1199±1212
1205
Figure 2. X-Ray structures of cephams 56, 62, and 64 with crystallographic numbering scheme.
65 by the addition of a second molecule of DMAD, although
this path appears to be less likely. Tetraester 67 is derived
from 66, which cannot rearrange to the corresponding ylide.
Compound 45 undergoes intramolecular cyclo-addition of
the hydroxy group to yield the diastereomeric pair 50 and
51. The exo-con®guration of methoxycarbonyl group at C-3
is preferred. Compound 67 as a result of the intramolecular
cyclization by addition of hydroxy group to the double bond
can form diaza-oxa-perhydroacenaphtene 68. Compounds
65±68 were not isolated and not even detected. Their exis-
tence is inferredby the assumedsimilarity to the analogous,
isolatedandcharacterizedcompounds
59, 61, 63, and 64.

1206
I. Pan®l et al. / Tetrahedron 58 +2002) 1199±1212
Scheme 10.
With notable exception of compound 55 6l-arabino con-
®guration), the formation of all other products can be easily
explainedfollowing Scheme 3. The pathway leading to the
formation of 55 is unclear andmay possibly be associated
with the presence of a minute amount of the alternative
diastereomer 6resulted from less probable cis-approach)
3. Experimental
Melting points were determined on a Koe¯er hot-stage
apparatus. H NMR spectra were recorded using Brucker
1
Avance 500 andVarian Gemini AC-200 instruments. IR
spectra were recorded on a Perkin±Elmer FT-IR Spectrum
2000 spectrophotometer. Mass spectra were recorded using
an AMD-604 Inectra GmbH spectrometer. Column
chromatography was performedusing Merck Kiesel Gel
6230±400 mesh).
which accompaniedformation of pyrazoliidn-3-ones
4
6XˆNH) during the reaction of lactone 2 andhydrazine.
Such adduct has been observed previously only in the
case of N-benzyl-hydrazine addition to the erythro-lactone
2 6R1ˆCH2OAc, R2ˆOAc).4,6 The alternative path leading
to the formation of 55 that involves epimerization at C-5 of
the pyrazolidin-3-one skeleton via the intramolecular retro-
Michael reaction is forbidden by the Baldwin rules 6Scheme
10).
3.1. Reaction of pyrazolidin-3-ones 13±15 and 18 with
butyl glyoxylate. General procedure
Pyrazolidin-3-ones 613±15, 18; 0.10 mmol), freshly
distilled butyl glyoxylate 60.12 mmol) and p-TsOH 62 mg)
in toluene 620 ml) were re¯uxedfor 0.5 h while the solvent
was slowly distilled off 615 ml). Subsequently the solution
was washedwith saturatedsodium bicarbonate andwater,
dried and evaporated. The residue was puri®ed by chroma-
tography using hexane±ethyl acetate 1:1 v/v as an eluent to
give products 21±24.
Bi- andtricyclic pyrazolidinones 21, 23, 25, 37, 40, 43, 48,
50, 52, 53 and 54 were evaluatedfor their biological
activity. An inhibition of the dd-carboxypeptidase activity
was measured.17±19 These compounds, however, did not
exhibit any signi®cant inhibitory activity. It can be
speculatedthat the polyol side chain that is present in all
investigatedcompounsd might be responsible for the
observedlack of biological activity.
3.1.1. ,2R,4S,5R,6S)-5-Acetoxy-4-acetoxymethyl-1,9-diaza-
9-benzyl-2-n-butoxycarbonyl-3-oxa-8-oxo-bicyclo[4.3.0]-
nonane ,21). 81%; Colorless crystals; mp 134±1368C;
[a]Dˆ118.9 6c 1.0, CH2Cl2); IR 6CHCl3): n 1744,
In summary, we have shown that the pyrazolidin-3-ones
having polyol side chain at C-5 carbon react with DMAD
to form bipyrazolidine compounds. The reaction proceeds
via addition of the amine nitrogen atom to a molecule of
DMAD. The adduct rearranges to the ylide which adds,
with a high stereoselectivity, the secondmolecule of
DMAD. The major reaction products are accompanied
by a number of by-products. Their isolation and identi®ca-
tion allowedus to formulate the probable reaction
pathway.
1700 cm21; H NMR 6CDCl3): d 7.34±7.25 6m, 5H, Ph),
1
5.18 6s, 1H, H-2), 5.06 6t, 1H, Jˆ9.5, 10.0 Hz, H-5), 4.87,
4.57 62d, 2H, Jˆ16.5 Hz, Bn), 4.32 6dt, 1H, Jˆ3.5, 3.5,
10.0 Hz, H-4), 4.06±4.17 6m, 1H, CO2CH2, CH2OAc),
3.88 6bt, 1H, H-6), 2.73 6dd, 1H, Jˆ8.0, 16.5 Hz, H-7),
2.54 6dd, 1H, Jˆ16.0 Hz, H-70), 2.10, 2.09 62s, 6H, 2Ac),
1.57, 1.30, 0.92 63m, 7H, C3H7); MS 6EI/HR) m/z
462.20237, M1; calcdfor C 23H30N2O8: 462.2002. Anal.

I. Pan®l et al. / Tetrahedron 58 +2002) 1199±1212
1207
calcdfor C 23H30N2O8: C, 59.74; H, 6.49; N, 6.06. Found: C,
59.63; H, 6.47; N, 5.95.
3.1.6. ,2S,3S,4R,6S,7R,8R)- and ,2S,3R,4R,6S,7R,8R)-
1,11-Diaza-2-butoxycarbonyl-7-t-butyl dimethylsiloxy-
3,4-dimethoxy carbonyl-6-methyl-5-oxa-tricyclo[6.3.00.0]-
undecan-10-one ,28,29) and ,2S,4S,5R,6R)-1,9-diaza-2-
butoxycarbonyl-5-t-butyldimethylsiloxy-4-methyl-3-oxa-
8-oxo-bicyclo[4.3.0]nonane ,30). Pyrazolidin-3-one 18
60.15 g, 0.60 mmol) in toluene 620 ml) was treatedwith
butyl glyoxylate 60.080 g, 0.60 mmol), DMAD 60.090 g,
0.60 mmol) and p-TsOH 65 mg). The mixture was re¯uxed
for 15 min, while 12 ml of the solvent were distilled off. The
remaining solution was evaporatedandresidue separatedby
chromatography using hexane±ethyl acetate 7:3 v/v as an
eluent to afford 30 60.05 g, 21%), 28 60.04 g, 13%) and 29
60.13 g, 40%).
3.1.2. ,2S,4S,5R,6S)-1,9-Diaza-5-benzyloxy-4-benzyloxy-
methyl-2-butoxycarbonyl-9-methyl-3-oxa-8-oxo-bicyclo-
[4.3.0]nonane ,22). 6%; Colorless oil; [a]Dˆ29.5 6c 0.9,
CH2Cl2); IR 6CHCl3): n 1746, 1702 cm21 1H NMR
;
6CDCl3): d 7.33±7.25 6m, 5H, Ph), 5.20 6dd, 1H, Jˆ6.0,
10.5 Hz, H-5), 4.89, 4.03 62d, 2H, Jˆ15.0 Hz, NBn), 4.61
6s, 1H, H-2), 4.26±4.12 6m, 4H, CH2OAc, CO2CH2), 4.08
6dt, 1H, Jˆ6.5, 7.0, 13.5 Hz, H-6), 3.95 6ddd, 1H, Jˆ3.0,
5.0, 10.5 Hz, H-4), 2.94 6dd, 1H, Jˆ13.5, 16.5 Hz, H-7),
2.21 6dd, 1H, Jˆ7.0, 16.5 Hz, H-70), 2.07, 2.04 62s, 6H,
2Ac), 1.62, 1.38, 0.94 63m, 7H, C3H7); MS 6EI/HR) m/z
462.20100, M1; calcdfor C 23H30N2O8: 462.20021.
Compound 28: colorless oil; [a]Dˆ263.9 6c 0.7, CH2Cl2);
IR 6CHCl3): n 1740, 1702 cm21; 1H NMR 6CDCl3): d 5.10
6d, 1H, Jˆ8.0 Hz, H-2), 4.46 6dq, 1H, Jˆ6.5, 7.0 Hz, H-6),
4.31 6d, 1H, Jˆ8.0 Hz, H-3), 4.19 6m, 2H, CO2CH2), 4.07
6m, 1H, H-8), 3.87 6dd, 1H, Jˆ2.5, 7.0 Hz, H-7), 3.79, 3.77
62s, 6H, 2OCH3), 3.24 6dd, 1H, Jˆ5.0, 18.0 Hz, H-9), 2.85
6dd, 1H, Jˆ6.0, 18.0 Hz, H-90), 1.64, 1.37, 0.94 63m, 7H,
C3H7), 1.36 6d, 1H, Jˆ6.5 Hz, CH3), 0.89 6s, 9H, t-Bu), 0.13,
0.08 62s, 6H, 2Me); MS 6LSIMS/HR) m/z 551.22439,
6M1Na)1; calcdfor C 24H40N9O2SiNa: 551.24005. Anal.
calcdfor C 24H40N9O2Si: C, 54.54; H, 7.57; N, 5.30.
Found: C, 55.26; H, 7.83; N, 5.15.
3.1.3. ,2R,4S,5R,6S)-1,9-Diaza-5-benzyloxy-4-benzyloxy-
methyl-2-butoxycarbonyl-9-methyl-3-oxa-8-oxo-bicyclo-
[4.3.0]nonane ,23). 44%; Colorless crystals; mp 72±738C;
[a]Dˆ23.0 6c 0.8, CH2Cl2); IR 6CHCl3): n 1743,
1695 cm21 1H NMR 6CDCl3): d 7.36±7.14 6m, 10H,
;
2£Ph), 5.26 6s, 1H, H-2), 4.66, 4.54 62d, 2H, Jˆ12.0 Hz,
Bn), 4.52, 4.48 62d, 2H, Jˆ11.0 Hz, Bn), 4.26±4.16 6m, 2H,
CO2CH2), 4.02 6ddd, 1H, Jˆ2.5, 3.5, 9.5 Hz, H-4), 3.79 6m,
1H, H-6), 3.76 6dd, 1H, Jˆ3.5, 11.0 Hz, CHAHBOBn), 3.71
6dd, 1H, Jˆ2.5, 11.0 Hz, CHAHBOBn), 3.63 6t, 1H, Jˆ9.5,
9.5 Hz, H-5), 3.00 6s, 3H, CH3), 2.70 6dd, 1H, Jˆ8.0,
16.5 Hz, H-7), 2.43 6d, 1H, Jˆ16.5 Hz, H-70), 1.67, 1.39,
0.93 63m, 7H, C3H7); MS 6EI/HR) m/z 482.241822, M1;
calcdfor C 27H34N2O6: 482.241682. Anal. calcdfor
C27H34N2O6: C, 67.21; H, 7.05; N, 5.80. Found: C, 67.12;
H, 7.05; N, 5.62.
Compound 29: colorless oil; [a]Dˆ136.7 6c 1.4, CH2Cl2);
IR 6CHCl3): n 1748, 1701 cm21; 1H NMR 6CDCl3): d 5.05
6d, 1H, Jˆ14.0 Hz, H-2), 4.44 6d, 1H, Jˆ14.0 Hz, H-3),
4.43 6dq, 1H, Jˆ6.0, 7.5 Hz, H-6), 4.12 6m, 2H, CO2CH2),
4.01 6ddd, 1H, Jˆ3.0, 5.0, 6.5 Hz, H-8), 3.85 6dd, 1H,
Jˆ3.0, 7.5 Hz, H-7), 3.77, 3.70 62s, 6H, 2OCH3), 3.27
6dd, 1H, Jˆ5.0, 18.0 Hz, H-9), 2.87 6dd, 1H, Jˆ6.0,
18.0 Hz, H-90), 1.61, 1.37, 0.94 63m, 7H, C3H7), 1.35 6d,
1H, Jˆ6.5 Hz, CH3), 0.89 6s, 9H, t-Bu), 0.13, 0.06 62s, 6H,
2Me); MS 6LSIMS/HR) m/z 551.23956, M1; calcdfor
3.1.4. ,2S,4R,5S,6R)-1,9-Diaza-5-t-butyldimethylsiloxy-
2-butoxycarbonyl-4,9-dimethyl-3-oxa-8-oxo-bicyclo-
[4.3.0]nonane ,24). 79%; Colorless oil; [a]Dˆ223.4 6c 1,
CH2Cl2); IR 6CHCl3): n 1743, 1695 cm21 1H NMR
;
6CDCl3): d 5.19 6s, 3H, H-2), 4.25 6m, 2H, CO2CH2), 3.72
6dq, 1H, Jˆ6.0, 9.0 Hz, H-4), 3.66 6bt, 2H, Jˆ8.0, 9.0 Hz,
H-6), 3.31 6t, 1H, Jˆ9.0, 9.5 Hz, H-5), 2.97 6s, 3H, CH3),
2.72 6dd, 1H, Jˆ8.0, 16.5 Hz, H-7), 2.56 6d, H, Jˆ16.5 Hz,
H-70), 1.69, 1.42, 0.96 63m, 7H, C3H7), 1.25 6d, 1H,
Jˆ6.0 Hz, CH3), 0.88 6s, 9H, t-Bu), 0.13, 0.10 62s, 6H,
2Me); MS 6EI/HR) m/z 400.23905, M1; calcdfor
C19H36N2O5Si: 400.23935. Anal. calcdfor C 19H36N2O5Si:
C, 57.0; H, 9.0; N, 7.0. Found: C, 57.16; H, 8.83; N, 7.34.
C24H40N2O9SiNa:
551.24005.
Anal.
calcdfor
C24H40N2O9Si: C, 54.54; H, 7.57; N, 5.30. Found: C,
55.63; H, 7.58; N, 5.26.
Compound 30: colorless oil; [a]Dˆ218.2 6c 0.53, CH2Cl2);
IR 6CHCl3): n 3387, 1741, 1702 cm21; 1H NMR 6CDCl3): d
4.98 6s, 1H, H-2), 4.22 6m, 2H, CO2CH2), 3.73 6dq, 1H,
Jˆ6.0, 9.0 Hz, H-4), 3.67 6bt, 1H, Jˆ8.0, 9.0 Hz, H-6),
3.47 6t, 1H, Jˆ9.0, 9.0 Hz, H-5), 2.79 6dd, 1H, Jˆ8.0,
17.0 Hz, H-7), 2.54 6d, H, Jˆ17.0 Hz, H-70), 1.68, 1.41,
0.95 63m, 7H, C3H7), 1.29 6d, 1H, Jˆ6.0 Hz, CH3), 0.88
6s, 9H, t-Bu), 0.13, 0.11 62s, 6H, 2Me); MS 6EI/HR) m/z
386.22360, M1; calcdfor C 18H34N2O5Si: 386.2237.
3.1.5. ,2S,4R,5S,6R)-1,9-Diaza-2-butoxycarbonyl-5-hy-
droxy-4,9-dimethyl-3-oxa-8-oxo-bicyclo [4.3.0]nonane
,25). To compound 24 60.080 g, 0.2 mmol) in THF 65 ml)
at room temperature was added Bu4NF´3H2O 60.063 g,
0.2 mmol) andresultedmixture was stirredfor 0.5 h. Subse-
quently, solvent was removed under reduced pressure and
residue puri®ed by chromatography to give compound 25
60.054 g, 95%); colorless crystals; mp 122±1238C;
[a]Dˆ17.2 6c 0.5, CH2Cl2); IR 6CHCl3): n 3400, 1741,
3.1.7.
,2S,4S,5R,6R)-1,9-Diaza-2-butoxycarbonyl-5-
hydroxy-4-methyl-3-oxa-8-oxo-bicyclo[4.3.0]nonane ,31).
Compound 31 was obtainedfrom 30 according to the pro-
cedure described for 25. 80%; Colorless crystals; mp 168±
1708C; [a]Dˆ243.8 6c 0.3, CH2Cl2); IR 6CHCl3): n 3388,
1
1692 cm21; H NMR 6CDCl3): d 5.20 6s, 1H, H-2), 4.24
1
6m, 2H, CO2CH2), 3.81 6dq, 1H, Jˆ6.0, 9.5 Hz, H-4), 3.70
6dd, 1H, Jˆ7.5, 9.5 Hz, H-6), 3.22 6t, 1H, Jˆ9.5 Hz, H-5),
2.98 6s, 3H, CH3), 2.76 6dd, 1H, Jˆ7.5, 16.5 Hz, H-7), 2.66
6d, 1H, Jˆ16.5 Hz, H-70), 1.70, 1.42, 0.97 63m, 7H, C3H7),
1.30 6d, 1H, Jˆ6.0 Hz, CH3); MS 6EI/HR) m/z 287.16157,
6M1H)1; calcdfor C 13H23N2O5: 287.16071.
1741, 1703 cm21; H NMR 6CDCl3): d 7.08 6bs, 1H, NH),
4.99 6s, 1H, H-2), 4.21 6m, 2H, CO2CH2), 3.87 6dq, 1H,
Jˆ6.0, 9.0 Hz, H-4), 3.71 6dd, 1H, Jˆ7.5, 9.5 Hz, H-6),
3.45 6dt, 1H, Jˆ6.0, 9.5, 9.5 Hz, H-57), 2.82 6dd, 1H,
Jˆ7.5, 17.0 Hz, H-7), 2.63 6dd, 1H, Jˆ5.0, 18.0 Hz, H-9),
3.79, 3.77 62s, 6H, 2OCH3), 3.24 6dd, 1H, Jˆ5.0, 18.0 Hz,

1208
I. Pan®l et al. / Tetrahedron 58 +2002) 1199±1212
H-9), 2.85 6d, 1H, Jˆ17.0 Hz, H-70), 1.68, 1.40, 0.96 63m,
7H, C3H7), 1.34 6d, 1H, Jˆ6.0 Hz, CH3); MS 6LSIMS/HR)
m/z 273.14504, 6M1H)1; calcdfor C 12H21N2O5: 273.14472.
for C30H42O6N2SiNa: 577.27331. Anal. calcdfor
C30H42N2O6Si: C, 64.98; H, 7.58; N, 5.05. Found: C,
64.88; H, 7.35; N, 4.99.
3.1.8. ,5S,10S,20R)-5-,20-t-Butyldimethylsiloxy-10,30-di-
benzyloxy)propyl-1-formyl-pyrazolidin-3-one ,32). Com-
pound 16 60.36 g, 1.0 mmol) in DMF 62.5 ml) was treated
with TBSCl 60.17 g, 1.1 mmol) andimiadzole 60.08 g,
1.1 mmol) andleft at room temperature for 3 h. Subse-
quently the mixture was pouredinto water andextracted
with t-butyl methyl ether. The extract was dried and evapo-
rated. The crude product was puri®ed by chromatography to
give 32 60.44 g, 90%); colorless crystals; mp 102±1048C;
[a]Dˆ279.0 6c 1.1, CH2Cl2); IR 6CHCl3): g 3395, 1716,
1667 cm21; 1H NMR 6CDCl3): d 7.85 6s, 1H, CHO), 7.41±
7.18 6m, 10H, 2£Ph), 4.66 6m, 1H, H-5), 4.64, 4.50 62d, 2H,
Jˆ11.0 Hz, Bn), 4.43 6bs, 2H, Bn), 3.91 6q, 1H, H-20), 3.82
6m, 1H, H-10), 3.53 6m, 2H, H-30a,30b), 2.89 6dd, 1H, Jˆ4.0,
17.5 Hz, H-4a), 2.77 6dd, 1H, Jˆ9.0, 17.5 Hz, H-4b), 0.88
6s, 9H, t-Bu), 0.05 62s, 6H, 2Me); MS 6LSIMS) m/z 499,
6M1H)1. Anal. calcdfor C 27H38N2O5Si: C, 65.06; H, 7.63;
N, 5.63. Found: C, 65.00; H, 7.66; N, 5.62.
3.1.12.
,3S,10S,20R)-3-,10,30-Dibenzyloxy-20-t-butyldi-
methylsiloxypropyl)-2,3-dihydro-6,7-dimethoxycarbonyl-
5,5-dimethyl-1H,5H-pyrazolo[1,2-a]pyrazol-1-one ,36).
Compound 34 60.047 g, 0.10 mmol) in methanol 62 ml)
was treatedwith dimethoxypropane 60.048 g, 0.40 mmol),
camphorsulfonic acid62.5 mg, 0.01 mmol) andre¯uxedfor
0.5 h. Subsequently methanol was evaporated, residue
dissolvedin acetonitrile 65 ml) andtreatedwith DMAD
60.016 g, 0.11 mmol). The mixture was stirredfor 3 h at
room temperature, evaporatedandpuri®edby chromato-
graphy using hexane±ethyl acetate 1:1 v/v as an eluent to
give 36 60.039 g, 59%); yellow oil; [a]Dˆ1171.9 6c 0.5,
CH2Cl2); IR 6CHCl3): n 1752, 1702 cm21 1H NMR
;
6CDCl3): d 7.35±7.24 6m, 10H, 2£Ph), 4.95, 4.60 62d, 2H,
Jˆ11.0 Hz, Bn), 4.49, 4.47 62d, 2H, Jˆ12.0 Hz, Bn), 4.08
6dd, 1H, Jˆ8.5, 10.5 Hz, H-3), 3.92 6s, 3H, OCH3), 3.53 6dd,
1H, H-30a), 3.47 6dd, 1H, H-30b), 3.32 6dd, 1H, Jˆ10.5,
17.3 Hz, H-2a), 2.65 6dd, 1H, Jˆ8.5, 17.5 Hz, H-2b),
1.59, 1.55 62s, 6H, 2CH3), 0.86 6s, 9H, t-Bu), 0.03 62s,
6H, 2Me); MS 6LSIMS/HR) m/z 675.31048, 6M1Na)1;
calcdfor C 35H48O8N2SiNa: 675.30777. Anal. calcdfor
C35H48O8N2Si: C, 64.41; H, 7.36; N, 4.29. Found: C,
64.44; H, 7.56; N, 4.08.
3.1.9. 2-N-Acetyl 33. Colorless oil; [a]Dˆ26.3 6c 1.7,
1
CH2Cl2); IR 6CHCl3): n 1767, 1723, 1695 cm21; H NMR
6CDCl3): d 8.39 6bs, 1H, CHO), 7.37±7.14 6m, 10H, 2£Ph),
5.08 6bs, 1H, H-5), 4.67, 4.37 62d, 2H, Jˆ11.5 Hz, Bn), 4.52
6s, 2H, Bn), 4.02 6m, 1H, H-20), 3.92 6m, 1H, H-10), 3.58 6dd,
1H, Jˆ5.5, 10.0 Hz, H-30a), 3.53 6dd, 1H, Jˆ5.0, 10.0 Hz,
H-30b), 3.04 6bd, 1H, H-4a), 2.85 6dd, 1H, Jˆ9.0, 17.5 Hz,
H-4b), 2.15 6bs, 3H, Ac), 0.90 6s, 9H, t-Bu), 0.07, 0.06 62s,
6H, 2Me); MS 6LSIMS) m/z 541, 6M1H)1. Anal. calcdfor
C29H40N2O6Si: C, 64.44; H, 7.40; N, 5.18. Found: C, 64.51;
H, 7.59; N, 4.99.
3.1.13. ,3S,5S,10S,20R)-3-,10,30-Dibenzyloxy-20-t-butyldi-
methylsiloxypropyl)-2,3-dihydro-5,6,7-trimethoxycar-
bonyl-5-methoxycarbonylmethyl-1H,5H-pyrazolo[1,2-
a]pyrazol-1-one ,37) and ,5S,10S,20R)-2-acetyl-5-,10,30-
dibenzyloxy-20-t-butyldimethylsiloxy)-1-,100,200-dimethyl-
oxycarbonylethylene)-pyrazolidin-3-one ,39). A mixture
of compound 34 60.094 g, 0.20 mmol), DMAD 60.064 g,
0.44 mmol) andcamphorsulfonic acid62 mg, 0.01 mmol)
in acetonitrile 65 ml) was stirredat room temperature for
3 h. Subsequently, solvent was evaporatedandthe residue
separatedon a silica gel column using hexane±ethyl acetate
1:1 v/v as an eluent to afford 37 60.119 g, 79%) and 38
67 mg, 6%), which was immediately acetylated with acetic
anhydride±pyridine mixture 61:1) to give acetate 39 68 mg).
3.1.10. ,5S,10S,20R)-5-,2-t-Butyldimethylsiloxy-10,30-di-
benzyloxy)propyl-pyrazolidin-3-one ,34). Compound 17
60.29 g, 1.0 mmol) in acetonitrile 62.5 ml) was silylated
with TBSCl 60.17 g, 1.1 mmol) andimiadzole 60.08 g,
1.1 mmol) andleft at room temperature for 0.5 h. Work-
up as for compound 32 provided 34 60.42 g, 89%); colorless
oil; [a]Dˆ221.3 6c 5.1, CH2Cl2); IR 6CHCl3): n 3434,
3240, 1698 cm21 1H NMR 6CDCl3): d 7.37±7.28 6m,
;
10H, 2£Ph), 6.50, 4.23 62bs, 2H, 2NH), 4.77, 4.45 62d,
2H, Jˆ11.5 Hz, Bn), 4.51 6s, 2H, Bn), 4.10 6dt, 1H, H-20),
3.88 6bs, 1H, H-5), 3.70 6dd, 1H, Jˆ3.5, 4.0 Hz, H-10), 3.52
6d, 2H, Jˆ5.0, 10.0 Hz, H-30a,30b), 2.74 6dd, 1H, Jˆ9.0,
16.5 Hz, H-4a), 2.38 6dd, 1H, Jˆ7.0, 16.5 Hz, H-4b), 0.88
6s, 9H, t-Bu), 0.07, 0.06 62s, 6H, 2Me); MS 6LSIMS) m/z
471.26791, 6M1H)1; calcdfor C 26H39N2O4Si: 471.26933.
Anal. calcdfor C 26H38N2O4Si: C, 66.38; H, 8.08; N, 5.95.
Found: C, 66.29; H, 7.95; N, 5.87.
Compound 37: pale yellow syrup; [a]Dˆ145.4 6c 1.7,
CH2Cl2); IR 6CHCl3): n 1738, 1709 cm21 1H NMR
;
6CDCl3): d 7.36±7.24 6m, 10H, 2£Ph), 4.79, 4.52 62d, 2H,
Jˆ11.0 Hz, Bn), 4.56, 4.48 62d, 2H, Jˆ12.0 Hz, Bn), 3.94
6s, 3H, CO2Me), 3.84±3.75 6m, 3H, H-5,10,20), 3.76, 3.76
62s, 6H, 2CO2Me), 3.55 6s, 3H, CO2Me), 3.51±3.44 6m, 2H,
CH2OBn), 3.28, 3.08 62d, 2H, Jˆ15.5 Hz, CH2CO2Me),
3.16 6dd, 1H, Jˆ7.0, 17.5 Hz, H-4a), 2.75 6dd, 1H, Jˆ9.5,
17.5 Hz, H-4b), 0.86 6s, 9H, t-Bu), 0.03, 0.00 62s, 6H, 2Me);
13C NMR 6CDCl3): d 169.54, 169.37, 168.44, 162.57,
159.12, 138.19, 137.96, 135.64, 128.33, 128.26, 127.98,
127.75, 127.69, 127.65, 127.58, 117.79, 80.46, 76.88,
74.37, 73.39, 72.27, 71.59, 58.58, 53.30, 53.14, 52.14,
51.75, 37.9, 334.26, 25.80, 18.01, 24.53, 24.86. MS
6LSIMS) m/z 755, 6M1H)1. Anal. calcdfor
C38H50N2O12Si: C, 60.47; H, 6.63; N, 3.71. Found: C,
60.33; H, 6.48; N, 3.67.
3.1.11. 1,2-Di-N-acetyl 35. Colorless oil; [a]Dˆ123.8 6c
1
0.6, CH2Cl2); IR 6CHCl3): n 1764, 1734, 1673 cm21; H
NMR 6CDCl3): d 7.38±7.14 6m, 10H, 2£Ph), 5.08 6bd,
1H, H-5), 4.67, 4.33 62d, 2H, Jˆ11.5 Hz, Bn), 4.56, 4.49
62d, 2H, Jˆ11.0 Hz, Bn), 4.01 6m, 1H, H-20), 3.94 6dd, 1H,
Jˆ2.0, 4.0 Hz, H-10), 3.59 6dd, 1H, Jˆ5.5, 10.0 Hz, H-30a),
3.53 6dd, 1H, Jˆ5.0, 10.0 Hz, H-30b), 3.03 6dd, 1H, Jˆ1.0,
17.5 Hz, H-4a), 2.81 6dd, 1H, Jˆ8.5, 17.5 Hz, H-4b), 2.07,
2.04 62s, 6H, 2Ac), 0.89 6s, 9H, t-Bu), 0.07, 0.05 62s, 6H,
2Me); MS 6LSIMS/HR) m/z 577.27099, 6M1Na)1; calcd
Compound 39: colorless oil; [a]Dˆ219.3 6c 0.2, CH2Cl2);
IR 6CHCl3): n 1726, 1619 cm21 1H NMR 6CDCl3): d
;

I. Pan®l et al. / Tetrahedron 58 +2002) 1199±1212
1209
7.36±7.23 6m, 10H, 2£Ph), 4.94 6s, 1H, H-200), 4.66, 4.43
62d, 2H, Jˆ11.5 Hz, Bn), 4.53, 4.48 62d, 2H, Jˆ10.0 Hz,
Bn), 4.39 6m, 1H, H-5), 3.92 6m, 2H, H-10,20), 3.84, 3.66 62s,
6H, 2CO2Me), 3.48 6m, 2H, H-30a,30b), 2.95 6d, 2H, H-
4a,4b), 2.07 6s, 3H, Ac), 0.88 6s, 9H, t-Bu), 0.05, 0.04 62s,
6H, 2Me); MS 6LSIMS/HR) m/z 677.28730, 6M1Na)1;
calcdfor C 34H46N2O9SiNa: 677.28703. Anal. calcdfor
C34H46N2O9Si: C, 62.38; H, 7.03; N, 4.28. Found: C,
62.42; H, 6.94; N, 4.11.
4H, H-4,6, CH2OBn), 3.44, 3.26 62d, 2H, Jˆ16.0 Hz,
CH2CO2Me), 3.18 6dd, 1H, Jˆ8.0, 16.5 Hz, H-7a), 2.74
6dd, 1H, Jˆ1.0, 16.5 Hz, H-7b), 2.23 6s, 3H, Ac); MS
6LSIMS/HR) m/z 563.2041, 6M1Na)1; calcdfor
C28H32N2O9Na: 563.2007.
3.1.15. ,2R,3S,4S,6S,7S,8S)- and ,2R,3R,4S,6S,7S,8S)-
1,11-Diaza-7-benzyloxy-6-benzyloxymethyl-2,3,4-tri-
methoxycarbonyl-2-methoxycarbonylmethyl-5-oxa-tri-
cyclo[6.3.00.0]undecan-10-one ,43 and 44). Compound 16
60.178 g, 0.05 mmol), DMAD 60.142 g, 0.1 mmol) and
p-TsOH 62 mg) in benzene 615 ml) were kept under re¯ux
while the solvent 612 ml) was slowly distilled off. Subse-
quently, residue was separated on a silica gel using hexane±
ethyl acetate 1:1 v/v as an eluent to yieldtwo products 43
60.06 g, 50%) and 44 60.04 g, 30%).
3.1.14. ,3S,5S,10S,20R)-3-,20-Acetoxy-10,30-dibenzyloxy-
propyl)-2,3-dihydro-5,6,7-trimethoxy carbonyl-5-meth-
oxycarbonylmethyl-1H,5H-pyrazolo[1,2-a]pyrazol-1-
one ,40), ,5S,10S,20R)-1-acetyl-5-,20-acetoxy-10,30-diben-
zyloxypropyl)-2-,100,200-dimethoxycarbonyl ethylene)-
pyrazolidin-3-one ,41) and ,2R,4R,5S,6S)-9-acetyl-1,3-
diaza-5-benzyloxy-4-benzyloxymethyl-2-methyloxycar-
bonyl-2-methoxycarbonylmethyl-3-oxa-8-oxo-bicyclo-
[4.3.0]nonane ,42). A mixture of compound 16 60.070 g,
0.20 mmol), DMAD 60.064 g, 0.44 mmol) andcamphor-
sulfonic acid65 mg) in acetonitrile 65 ml) was stirredat
room temperature for 3 h. Subsequently, solvent was evapo-
rated and the residue acetylated with acetic anhydride±
pyridine 61:1) mixture. The mixture of acetates was
separatedby chromatography using hexane±ethyl acetate
1:1 v/v as an eluent to affordthree products 40 60.103 g,
76%), 41 60.006 g, 5%) and 42 60.002 g, 2%).
Compound 43: more polar; colorless oil; [a]Dˆ191.3 6c
1
0.4, CH2Cl2); IR 6CHCl3): n 1740, 1701 cm21; H NMR
6C6D6): d 7.25±7.05 6m, 10H, 2£Ph), 4.55 6ddd, 1H,
Jˆ2.5, 3.0, 8.5 Hz, H-6), 4.41, 4.29 62d, 2H, Jˆ11.5 Hz,
Bn), 4.31, 4.17 62d, 2H, Jˆ12.0 Hz, Bn), 4.27 6m, 1H,
H-8), 4.19 6s, 1H, H-3), 3.75 6dd, 1H, Jˆ3.0, 8.5 Hz,
H-7), 3.57 6dd, 1H, Jˆ4.0, 17.5 Hz, H-9), 3.49 6dd, 1H,
Jˆ2.5, 11.0 Hz, CHAHBOBn), 3.47 6dd, 1H, Jˆ3.0,
11.0 Hz, CHAHBOBn), 3.35, 3.32, 3.20, 3.05 64s, 12H,
4£CO2Me), 3.05 62d, 2H, Jˆ17.5 Hz, CH2CO2Me), 2.56
6dd, 1H, Jˆ17.5 Hz, H-90); MS 6LSIMS/HR) m/z
Compound 40: pale yellow syrup; [a]Dˆ166.5 6c 1.4,
663.21530, 6M1Na)1; calcdfor
C
32H36N2O12Na:
CH2Cl2); IR 6CHCl3): n 1738, 1710 cm21
;
1H NMR
663.21659. Anal. calcdfor C 32H36N2O12: C, 60.00; H,
5.62; N, 4.37. Found: C, 60.19; H, 5.81; N, 4.21.
6C6D6): d 7.40±7.15 6m, 10H, 2£Ph), 5.14 6ddd, 1H,
Jˆ3.5, 4.5, 7.0 Hz, H-20), 4.85, 4.60 62d, 2H, Jˆ11.0 Hz,
Bn), 4.31, 4.24 62d, 2H, Jˆ12.0 Hz, Bn), 4.02 6dd, 1H,
Jˆ1.0, 7.0 Hz, H-10), 3.78 6ddd, 1H, Jˆ1.0, 7.5, 10.0 Hz,
H-3), 3.56, 3.34, 3.30, 3.24 64s, 12H, 4£OMe), 3.55 6dd, 1H,
Jˆ4.5, 10.5 Hz, H-30a), 3.50 6dd, 1H, Jˆ3.5, 10.5 Hz,
H-30b), 3.40 6s, 2H, CH2CO2Me), 3.17 6dd, 1H, Jˆ7.5,
18.0 Hz, H-2a), 2.75 6dd, 1H, Jˆ10.0, 18.0 Hz, H-2b),
1.69 6s, 3H, Ac); MS 6LSIMS/HR) m/z 705.22992,
6M1Na)1; calcdfor C 34H38N2O13Na: 705.22716. Anal.
calcdfor C 34H38N2O13: C, 59.82; H, 5.57; N, 4.10. Found:
C, 59.77; H, 5.74; N, 4.06.
Compound 44: less polar; colorless oil; [a]Dˆ1188.0 6c
1
0.2, CH2Cl2); IR 6CHCl3): n 1740, 1703 cm21; H NMR
6C6D6): d 7.30±7.05 6m, 10H, 2£Ph), 5.04 6s, 1H, H-3),
4.67 6dt, 1H, Jˆ2.5, 2.5, 8.0 Hz, H-6), 4.43, 4.42 62d, 2H,
Jˆ11.9 Hz, Bn), 4.31, 4.13 62d, 2H, Jˆ12.0 Hz, Bn), 4.25
6dt, 1H, Jˆ3.5, 5.0, 5.5 Hz, H-8), 3.79 6dd, 1H, Jˆ3.5,
8.0 Hz, H-7), 3.40 6dd, 1H, Jˆ2.5, 11.5 Hz, CHAHBOBn),
3.38 6dd, 1H, Jˆ2.5, 11.5 Hz, CHAHBOBn), 3.37, 3.28,
3.22, 3.15 64s, 12H, 4£CO2Me), 3.34, 3.16 62d, 2H,
Jˆ17.5 Hz, CH2CO2Me), 3.18 6dd, 1H, Jˆ5.0, 17.5 Hz,
H-9), 2.45 6dd, 1H, Jˆ5.5, 17.5 Hz, H-90); MS 6LSIMS/
HR) m/z 663.21662, 6M1Na)1; calcdfor C 32H36N2O12Na:
663.21659. Anal. calcdfor C 32H36N2O12: C, 60.00; H, 5.62;
N, 4.37. Found: C, 60.04; H, 5.74; N, 4.27.
Compound 41: colorless crystals; mp 49±518C; [a]Dˆ
250.2 6c 1.1, CH2Cl2); IR 6CHCl3): n 1742, 1620 cm21
;
1H NMR 6CDCl3): d 7.36±7.22 6m, 10H, 2£Ph), 5.11
6ddd, 1H, Jˆ4.5, 4.5, 6.0 Hz, H-20), 4.96 6s, 1H, H-200),
4.67, 4.42 62d, 2H, Jˆ11.0 Hz, Bn), 4.52, 4.49 62d, 2H,
Jˆ12.0 Hz, Bn), 4.30 6ddd, 1H, Jˆ1.0, 2.5, 8.5 Hz, H-5),
4.04 6dd, 1H, Jˆ2.5, 6.0 Hz, H-20), 3.87, 3.67 62s, 6H,
2£CO2Me), 3.65 6dd, 1H, Jˆ4.5, 11.0 Hz, H-20a), 3.62
6dd, 1H, Jˆ4.5, 11.0 Hz, H-20b), 2.98 6dd, 1H, Jˆ8.5,
17.5 Hz, H-4a), 2.86 6dd, 1H, Jˆ1.0, 17.5 Hz, H-4b),
2.10, 2.09 62s, 6H, 2Ac); MS 6LSIMS/HR) m/z 605.2128,
6M1Na)1; calcdfor C 30H34N2O10Na: 605.2106. Anal. calcd
for C30H34N2O10: C, 61.85; H, 5.84; N, 4.81. Found: C,
61.86; H, 6.00; N, 4.82.
3.1.16. ,3R,5R,10R,20S)- and ,3R,5S,10R,20S)-3-,20-Acet-
oxy-10-benzyloxy-propyl)-2,3-dihydro-5,6,7-trimethoxy-
carbonyl-5-methoxycarbonylmethyl-1H,5H-pyrazolo-
[1,2-a]pyrazol-1-one ,48 and 49) and ,5R,10R,20S)-5-,10-
benzyloxy-20-hydroxypropyl)-1-,100,200-dimethoxy carbo-
nylethylidene)-pyrazolidin-3-one ,47). Pyrazolidinone 20
60.050 g, 0.20 mmol) was treatedwith DMAD 60.064 g,
0.44 mmol) andcamphorsulfonic acid65 mg) in acetonitrile
65 ml) according to the procedure described for 40. Chro-
matographic separation using ethyl acetate as an eluent led
to three products 45 60.68 g, 65%), 46 60.064 g, 6%) and 47
60.016 g, 4%). Compounds 45 and 46 were acetylatedwith
acetic anhydride±pyridine mixture and characterized as
acetates 48 and 49.
Compound 42: colorless syrup; [a]Dˆ153 6c 0.33,
CH2Cl2); IR 6CHCl3): n 1746, 1641 cm21 1H NMR
;
6CDCl3): d 7.38±7.15 6m, 10H, 2£Ph), 4.68, 4.56 62d, 2H,
Jˆ12.0 Hz, Bn), 4.61, 4.55 62d, 2H, Jˆ11.5 Hz, Bn), 4.14
6bt, 1H, H-5), 3.84, 3.66 62s, 6H, 2£CO2Me), 3.85±3.60 6m,
Compound 47: colorless crystals; mp 135±1378C;

1210
I. Pan®l et al. / Tetrahedron 58 +2002) 1199±1212
[a]Dˆ1330.5 6c 1.4, CH2Cl2); IR 6CHCl3): n 3433, 1741,
6LSIMS/HR) m/z 557.17499, 6M1Na)1; calcdfor
C25H30N2O11Na: 557.17473.
1
1701 cm21; H NMR 6CDCl3): d 7.36±7.22 6m, 5H, Ph),
6.09 6bd, 1H, Jˆ9.0 Hz, H-5), 4.54, 4.44 62d, 2H,
Jˆ11.0 Hz, Bn), 3.99, 3.94 62d, 2H, Jˆ16.5 Hz,
CH2CO2Me), 3.87, 3.66 62s, 6H, 2£CO2CH3), 3.84±3.84
6m, 1H, H-20), 3.82 6dd, 1H, Jˆ1.0, 6.5 Hz, H-10), 3.07
6dd, 1H, Jˆ2.0, 16.5 Hz, H-4a), 2.76 6dd, 1H, Jˆ9.0,
16.5 Hz, H-4b), 1.31 6d, 3H, Jˆ6.0 Hz, CH3), 1.23 6d, 3H,
Jˆ6.5 Hz, CH3); MS 6LSIMS/HR) m/z 393.16655,
6M1H)1; calcdfor C 19H25N2O7: 393.16618.
3.1.18. ,3R,5R,10R,20S)-3-,10-Acetoxy-20-hydroxypropyl)-
2,3-dihydro-5,6,7-trimethoxycarbonyl-5-methoxycar-
bonylmethyl-1H,5H-pyrazolo[1,2-a]pyrazol-1-one ,52),
,3R,5R,10R,20S)-3-,20-acetoxy-10-hydroxypropyl)-2,3-
dihydro-5,6,7-trimethoxycarbonyl-5-methoxy carbonyl-
methyl-1H,5H-pyrazolo[1,2-a]pyrazol-1-one ,53), ,Z)-4-
O-acetyl-2,3,6-trideoxy-3-[10-N-,10,20-dimethoxycar-
bonylethylene)-hydrazino]-l-arabino-hexaldono-1,5-
lactone ,55), ,3R,5S,10R,20S)-3-,10-acetoxy-20-hydroxy-
propyl)-2,3-dihydro-5,6,7-trimethoxy carbonyl-5-meth-
oxycarbonylmethyl-1H,5H-pyrazolo[1,2-a]pyrazol-1-
one ,57), ,Z)-,5R,10R,20S)-5-,10-acetoxy-20-hydroxypro-
pyl)-1-,10,20-dimethoxycarbony-lethylene)-pyrazolidin-
3-one ,59), ,Z)-,5R,10R,20S)-5-,10-acetoxy-20-hydroxy-
propyl)-2-,10,20-dimethoxycarbonylethylene)-pyrazoli-
din-3-one ,61), ,3R,5R,10R,20S)-3-,10-acetoxy-20-hydroxy-
propyl)-2,3,7,8-tetrahydro-5,6,7,8-tetramethoxycarbonyl-
1H-pyrazolo[1,2-a] pyridazin-1-one ,63), ,8aR,8R,7S,
5aS,5R,4R,3S)-8-acetoxy-2a,8b-diaza-octahydro-3,4,5,5a-
tetramethoxycarbonyl-7-methyl-6-oxa-acenaphthylen-
2-one ,64). Compound 10 60.34 g, 0.20 mmol) and
anhydrous hydrazine 60.10 g, 0.30 mmol) in methanol
were stirredat room temperature for 3 h. Subsequently,
methanol was evaporated and residue dissolved in aceto-
nitrile 615 ml) andtreatedwith DMAD 60.064 g,
0.44 mmol) and p-TsOH 63 mg). The mixture was re¯uxed
for 15 min. Subsequently, it was evaporatedandseparated
on a silica gel column using hexane±ethyl acetate 1:1 v/v
mixture followedby 3:7 v/v mixture as eluents. Following
products were obtained: 52 662%), 53 68%), 55 65%), 57
63%), 59 64%), 61 65%), 63 63.5%).
Compound 48: pale yellow oil; [a]Dˆ275.5 6c 0.4,
CH2Cl2); IR 6CHCl3): n 1738, 1632 cm21 1H NMR
;
6CDCl3): d 7.36±7.27 6m, 5H, Ph), 4.98 6dq, 1H, Jˆ5.5,
6.5 Hz, H-20), 4.79, 4.67 62d, 2H, Jˆ11.0 Hz, Bn), 3.95,
3.82, 3.76, 3.60 64s, 12H, 4CO2CH3), 3.65 6ddd, 1H,
Jˆ1.0, 8.5, 9.0 Hz, H-3), 3.57 6dd, 1H, Jˆ1.0, 5.5 Hz,
H-10), 3.24, 3.17 62d, 2H, Jˆ16.0 Hz, CH2CO2Me), 3.23
6dd, 1H, Jˆ8.5, 17.5 Hz, H-2a), 2.76 6dd, 1H, Jˆ9.0,
17.5 Hz, H-2b), 2.04 6s, 3H, Ac), 1.25 6d, 3H, Jˆ6.5 Hz,
CH3); MS 6LSIMS/HR) m/z 599.18779, 6M1Na)1; calcd
for C27H32N2O12Na: 599.18529.
Compound 49: pale yellow oil; [a]Dˆ1291.5 6c 0.7,
CH2Cl2); IR 6CHCl3): n 1738, 1612 cm21 1H NMR
;
6CDCl3): d 7.36±7.27 6m, 5H, Ph), 4.92 6dq, 1H, Jˆ6.0,
6.5 Hz, H-20), 4.81, 4.66 62d, 2H, Jˆ11.5 Hz, Bn), 4.48
6ddd, 1H, Jˆ1.0, 8.0, 10.5 Hz, H-3), 4.12, 3.44 62d, 2H,
Jˆ18.0 Hz, CH2CO2Me), 3.84, 3.75, 3.68, 3.67 64s, 12H,
4£CO2CH3), 3.60 6dd, 1H, Jˆ1.0, 6.0 Hz, H-10), 3.21 6dd,
1H, Jˆ8.0, 17.0, 5.5 Hz, H-2a), 2.87 6dd, 1H, Jˆ10.5,
17.0 Hz, H-2b), 2.01 6s, 3H, Ac), 1.23 6d, 3H, Jˆ6.5 Hz,
CH3); MS 6LSIMS/HR) m/z 577.20511, 6M1H)1; calcdfor
C27H33N2O12: 577.20335.
3.1.17. ,2S,3R,4R,6R,7R,8R)- and ,2S,3S,4R,6R,7R,8R)-
Compound 52: pale yellow oil; [a]Dˆ2110.4 6c 2, CH2Cl2);
IR 6CHCl3): n 3509, 1738 cm21; 1H NMR 6CDCl3): d 4.80
6dd, 1H, Jˆ1.5, 8.0 Hz, H-10), 4.58 6ddd, 1H, Jˆ1.5, 8.5,
10.5 Hz, H-3), 3.97, 3.78, 3.70, 3.66 64s, 12H, 4£CO2CH3),
2.13 6s, 3H, Ac), 1.24 6d, 3H, Jˆ6.5 Hz, CH3); MS 6LSIMS/
HR) m/z 487.15585, 6M1H)1; calcdfor C 20H27N2O12:
487.15640.
1,11-Diaza-7-benzyloxy-2,3,4-trimethoxy
carbonyl-2-
methoxycarbonylmethyl-6-methyl-5-oxa-tricyclo[6.3.00.0]-
undecan-10-one ,50 and 51). Compounds 50 and 51
were obtained according to the procedure described for 43
and 44.
Compound 50: 78%; colorless oil; [a]Dˆ287.0 6c 0.5,
CH2Cl2); IR 6CHCl3): n 1737, 1703 cm21
;
1H NMR
Compound 53: pale yellow oil; [a]Dˆ2108.4 6c 0.9,
1
6C6D6): d 7.20±7.05 6m, 5H, Ph), 4.60 6dq, 1H, Jˆ6.5,
8.0 Hz, H-6), 4.26 6ddd, 1H, Jˆ3.0, 4.0, 6.0 Hz, H-8),
4.19, 4.12 62d, 2H, Jˆ12.0 Hz, Bn), 4.09 6s, 1H, H-3),
3.61 6dd, 1H, Jˆ4.0, 18.0 Hz, H-9a), 3.35, 3.31, 3.23,
3.04 64s, 12H, 4CO2CH3), 3.06, 2.85 62d, 2H, Jˆ18.0 Hz,
CH2CO2Me), 2.91 6dd, 1H, Jˆ3.0, 8.0 Hz, H-7), 2.59 6dd,
1H, Jˆ6.0, 17.7 Hz, H-9b), 1.09 6d, 3H, Jˆ6.5 Hz, CH3);
MS 6LSIMS/HR) m/z 535.19370, 6M1H)1; calcdfor
C25H31N2O11: 535.19279.
CH2Cl2); IR 6CHCl3): n 3463, 1737, 1711 cm21; H NMR
6C6D6): d 4.78 6dq, 1H, Jˆ6.5, 7.5 Hz, H-20), 3.82 6dd, 1H,
Jˆ1.5, 8.0 Hz, H-10), 4.46 6ddd, 1H, Jˆ1.5, 7.5, 11.0 Hz,
H-3), 3.58, 3.30, 3.27, 3.23 64s, 12H, 4£CO2CH3), 1.55 6s,
3H, Ac), 1.23 6d, 3H, Jˆ6.5 Hz, CH3); MS 6LSIMS/HR) m/z
509.14036, 6M1Na)1; calcdfor
C
20H26N2O12Na:
509.13834. Anal. calcdfor C 20H26N2O12: C, 49.38; H,
5.34; N, 5.76. Found: C, 49.45; H, 5.39; N, 5.83.
Compounds 52 and 53 were acetylatedwith acetic
anhydride±pyridine 61:1) mixture and gave in each case
the same product 54: pale yellow crystals; mp 140±
1428C; [a]Dˆ2114 6c 1.6, CH2Cl2); IR 6CHCl3): n 1741,
1709, 1635 cm21; 1H NMR 6C6D6): d 5.23 6dd, 1H, Jˆ1.5,
5.5 Hz, H-10), 5.06 6dq, 1H, Jˆ5.5, 6.5 Hz, H-20), 3.77 6ddd,
1H, Jˆ1.5, 8.5, 9.5 Hz, H-3), 3.56, 3.36, 3.28, 3.26 64s, 12H,
4CO2CH3), 3.47, 3.39 62d, 2H, Jˆ15.5 Hz, CH2CO2Me),
2.95 6dd, 1H, Jˆ9.5, 17.0 Hz, H-2a), 2.64 6dd, 1H, Jˆ8.5,
17.0 Hz, H-2b), 1.83, 1.58 62s, 6H, 2Ac), 0.94 6d, 3H,
Compound 51: 22%; colorless oil; [a]Dˆ2313.3 6c 0.3,
CH2Cl2); IR 6CHCl3): n 1740, 1704 cm21 1H NMR
;
6C6D6): d 7.20±7.06 6m, 5H, Ph), 5.08 6s, 1H, H-3), 4.84
6dq, 1H, Jˆ6.5, 8.5 Hz, H-6), 4.38, 4.24 62d, 2H,
Jˆ11.5 Hz, Bn), 4.19 6ddd, 1H, Jˆ3.5, 4.0, 6.0 Hz, H-8),
3.43, 3.34, 3.29, 3.26 64s, 12H, 4£CO2CH3), 3.36, 3.23 62d,
2H, Jˆ17.5 Hz, CH2CO2Me), 3.21 6dd, 1H, Jˆ4.0, 17.5 Hz,
H-9a), 3.02 6dd, 1H, Jˆ3.5, 8.5 Hz, H-7), 2.55 6dd, 1H,
Jˆ6.0, 17.5 Hz, H-9b), 1.15 6d, 3H, Jˆ6.5 Hz, CH3); MS

I. Pan®l et al. / Tetrahedron 58 +2002) 1199±1212
1211
Jˆ6.5 Hz, CH3); MS 6LSIMS/HR) m/z 551.14722,
6M1Na)1; calcdfor C 22H28N2O13Na: 551.14891. Anal.
calcdfor C 22H28N2O13: C, 50.00; H, 5.30; N, 5.30. Found:
C, 50.05; H, 5.57; N, 5.15.
octahydro-3,4,5,5a-tetramethoxy carbonyl-7-methyl-6-
oxa-perhydroacenaphthylen-2-one ,64). Compound 63
60.050 g, 0.10 mmol) and p-TsOH 63 mg) were dissolved
in toluene 615 ml) andre¯uxedfor 0.5 h while 8 ml of
toluene was distilled off. The residue was puri®ed by chro-
matography to give 64 60.039 g, 80%): colorless crystals;
mp 181±1838C; [a]Dˆ256.7 6c 0.8, CH2Cl2); IR 6CHCl3):
Compound 55 was characterizedafter acetylation with
acetic anhydride-pyridine 61:1) mixture to give 56 as color-
less crystals; mp 214±2178C; [a]Dˆ217.4 6c 1.3, CH2Cl2);
IR 6CHCl3): n 3331, 1746 cm21; 1H NMR 6CDCl3): d 4.84
6s, 1H, H-200), 4.76 6dd, 1H, Jˆ9.5, 10.0 Hz, H-4), 4.34 6dq,
1H, Jˆ6.5, 9.5 Hz, H-5), 3.91, 3.64 62s, 6H, 2£CO2CH3),
3.84 6m, 1H, H-3), 3.11 6dd, 1H, Jˆ7.0, 18.5 Hz, H-2a),
2.75 6dd, 1H, Jˆ10.0, 18.5 Hz, H-2b), 2.18, 2.08 62s, 6H,
2Ac), 1.40 6d, 3H, Jˆ6.5 Hz, CH3); MS 6LSIMS/HR) m/z
1
n 1750 cm21; H NMR 6C6D6): d 5.46 6d, 1H, Jˆ5.0 Hz,
H-3), 4.02 6ddd, 1H, Jˆ9.5, 10.0 Hz, H-8), 4.52 6dq, 1H,
Jˆ6.5, 10.0 Hz, H-7), 3.82 6d, 1H, Jˆ12.5 Hz, H-3), 3.66
6dd, 1H, Jˆ5.0, 12.5 Hz, H-4), 3.40, 3.35, 3.34, 3.17 64s,
12H, 4CO2CH3), 3.31 6dd, 1H, Jˆ7.0, 9.5 Hz, H-8a), 2.48
6dd, 1H, Jˆ7.0, 16.0 Hz, H-1a), 2.34 6d, 1H, Jˆ16.0 Hz,
H-1b), 1.50 6s, 3H, Ac), 1.10 6d, 3H, Jˆ6.1 Hz, CH3); MS
6LSIMS/HR) m/z 487.15611, 6M1H)1; calcdfor
C20H27N2O12: 487.15640.
409.12264, 6M1Na)1; calcdfor
C
16H22N2O9Na:
409.12230.
Compound 57 was characterizedas id-acetate
58; pale
3.2. Assay of dd-carboxypeptidase activity
yellow oil, [a]Dˆ1211.8 6c 0.4, CH2Cl2); IR 6CHCl3): n
1745, 1621 cm21; 1H NMR 6CDCl3): d 5.06 6dd, 1H, Jˆ1.5,
6.0 Hz, H-10), 5.00 6quintet, 1H, H-20), 4.48 6ddd, 1H,
Jˆ1.5, 9.0, 9.5 Hz, H-3), 3.99, 3.79, 3.70, 3.64 64s, 12H,
4£CO2CH3), 3.21, 3.11 62d, 2H, Jˆ15.0 Hz, CH2CO2Me),
3.16 6dd, 1H, Jˆ9.0, 17.5 Hz, H-2a), 2.82 6dd, 1H, Jˆ9.5,
17.5 Hz, H-2b), 2.15, 2.06 62s, 6H, 2Ac), 1.24 6d, 1H,
Jˆ6.0 Hz, CH3); MS 6LSIMS/HR) m/z 551.14857,
6M1Na)1; calcdfor C 22H28N2O13Na: 551.14891.
The enzyme activity was measuredas esdcribed
previously.18,19 Samples for assay of the dd-carboxypepti-
dase activity consisted of 10 ml of dd-carboxypeptidase
from Saccharopolyspora erythraea PZHTZ 64-575
640 units/mg), 20 ml of substrate solution containing
4.52 mg/ml Na,Ne-diacetyl-l-lysyl-d-alanyl-d-alanine in
0.1 M phosphate buffer, pH 8.0 and10 ml of 0.1 M
phosphate buffer, pH 8.0. Standard sample contained
20 ml of d-alanine in distilled water.
Compound 59 was characterizedas tri-acetate 60; colorless
oil, [a]Dˆ125.5 6c 0.6, CH2Cl2); IR 6CHCl3): n 1740,
1624 cm21 1H NMR 6CDCl3): d 5.11 6s, 1H, H-200),
;
Reaction mixture for assay of the dd-carboxypeptidase
activity consistedof 60 ml of 0.05 mg/ml ¯avin adenine
dinucleotide in 0.1 M phosphate buffer, pH 8.0, 10 ml of
0.05 mg/ml horseradish peroxidase 61230 units/mg) in
distilled water, 5 ml of 5 mg/ml o-dianisidine in methanol,
and2 ml of 11.77 mg/ml d-amino acidoxidase from porcine
kidney 66.7 units/mg) in 0.1 M phosphate buffer, pH 8.0.
5.09±5.03 6m, 2H, H-5,20), 4.31 6dd, 1H, Jˆ3.5, 8.5 Hz,
H-10), 3.93, 3.68 62s, 6H, 2CO2CH3), 3.08 6dd, 1H, Jˆ8.5,
17.5 Hz, H-4a), 2.69 6dd, 1H, Jˆ0.5, 17.5 Hz, H-4b), 2.45
6s, 3H, NAc), 2.04 6s, 6H, 2Ac), 1.21 6d, 3H, Jˆ6.5 Hz,
CH3); MS 6LSIMS/HR) m/z 451.12949, 6M1Na)1; calcd
for C18H24N2O10Na: 451.13116. Anal. calcdfor
C18H24N2O10: C, 50.46; H, 5.60; N, 6.54. Found: C, 50.33;
H, 5.64; N, 6.54.
Samples were incubatedfor 30 min at 37 8C andthen boiled
for 2 min. After cooling, 77 ml of the reaction mixture was
added, and all samples were incubated for 10 min at 378C.
Then to each sample was added 350 ml of mixture consist-
ing of methanol, distilled water and sulfuric acid 65:5:6 by
volume). Extinction of resultedsolution was measuredat
540 nm.
Compound 61 was characterizedas tri-acetate 62; colorless
crystals; mp 53±558C; [a]Dˆ211.5 6c 1.7, CH2Cl2); IR
1
6CHCl3): n 1738, 1664 cm21; H NMR 6CDCl3): d 5.33
6dd, 1H, Jˆ3.0, 5.5 Hz, H-10), 5.14 6dq, 1H, Jˆ3.0,
6.5 Hz, H-20), 5.02 6bs, 1H, H-5), 3.81, 3.77 62s, 6H,
2CO2CH3), 2.96 6dd, 1H, Jˆ9.5, 17.0 Hz, H-4a), 2.65 6bd,
1H, Jˆ17.0 Hz, H-4b), 2.17, 2.05, 2.04 63s, 9H, 3Ac), 1.36
6d, 3H, Jˆ6.5 Hz, CH3); MS 6LSIMS/HR) m/z 451.13131,
6M1Na)1; calcdfor C 18H24N2O10Na: 451.13287. Anal.
calcdfor C 18H24N2O10: C, 50.46; H, 5.60; N, 6.54. Found:
C, 50.61; H, 6.05; N, 6.34.
The inhibition of dd-peptidase 64-575 by the discussed
above pyrazolidinones was evaluated.20 Mixtures of 10 ml
of dd-peptidase 64-575 640 units/mg), 5 ml solution of pyra-
zolidinones in methanol and 5 ml of 0.1 M phosphate buffer,
pH 8.0 were incubatedfor 45 min at 37 8C. The concentra-
tion of pyrazolidinones in the mixture was from 0.025 to
0.00025 M. After incubation 20 ml of substrate solution was
added to 20 ml of each sample andresultedmixtures were
incubatedagain. The following pyrazolidnones were
tested: 21, 23, 25, 37, 40, 43, 48, 50, 52, 53 and 54. At
concentration of 0.025 M, none of testedcompounsd
exhibitedmeasurable inhibition activity.
Compound 63: colorless oil; [a]Dˆ142.7 6c 1.9, CH2Cl2);
1
IR 6CHCl3): n 3400, 1745 cm21; H NMR 6C6D6): d 5.22
6dd, 1H, Jˆ1.5, 8.0 Hz, H-10), 4.51 6dt, 1H, H-4), 3.82 6d,
1H, Jˆ3.0 Hz, H-9), 3.66, 3.45, 3.43, 3.41 64s, 12H,
4CO2CH3), 3.29 6d, 1H, Jˆ3.0 Hz, H-8), 3.16 6m, 1H, H-
20), 2.70 6dd, 1H, Jˆ9.5, 16.5 Hz, H-3a), 2.44 6bd, 1H,
Jˆ16.5 Hz, H-3b), 1.86 6s, 3H, Ac), 0.82 6d, 3H,
Jˆ6.5 Hz, CH3); MS 6LSIMS/HR) m/z 509.14047,
6M1Na)1; calcdfor C 20H26N2O12Na: 509.13834.
Acknowledgements
3.1.19. ,3S,4R,5R,5aS,7S,8R,8aR)-8-Acetoxy-2a,8b-diaza-
Authors are kindly indebted to the State Committee for

1212
I. Pan®l et al. / Tetrahedron 58 +2002) 1199±1212
7. Claramunt, R. M.; Elguero, J. Org. Prepr. Proc. Int. 1991, 23,
275±320.
Scienti®c Research. Grant 3T 09A 13112 for support of this
work.
8. Grashey, R. In 1,3-Dipolar Cycloaddition Chemistry, Padwa,
A., Ed.; Wiley: New York, 1984; pp. 733±815.
9. Acheson, R. M. Adv. Heterocycl. Chem. 1963, 1, 125±165.
10. George, M. V.; Khetan, S. K.; Gupta, R. K. Adv. Heterocycl.
Chem. 1976, 19, 279±371.
References
1. Marchand-Brynaert, J.; Ghosez, L. In Recent Progress in the
Chemical Synthesis of Antibiotics, Lukacs, G., Ohno, M., Eds.;
Springer: Berlin, 1990; pp. 727±797. Marchand-Brynaert, J.;
Baunkhala-Khrounz, Z.; Carretero, J. C.; Davies, J.; Ferrand,
D.; van Keulen, B. J.; Serckx-Poncin, B.; Ghosez, L.
Recent Advances in the Chemistry of b-lactam Antibiotics,
Vol. 70; 1998 Chem. Soc. 6Special Public.) 157±170.
2. Jungheim, L. N.; Sigmund, S. K. J. Org. Chem. 1987, 52,
4007±4013. Jungheim, L. N.; Sigmund, S. K.; Fisher, J. W.
Tetrahedron Lett. 1987, 28, 285±288. Ternansky, R. J.;
Draheim, S. E. Tetrahedron Lett. 1988, 29, 6569±6572.
Ternansky, R. J.; Draheim, S. E. Tetrahedron Lett. 1990, 31,
2805±2808. Holmes, R. E.; Neel, D. A. Tetrahedron Lett.
1990, 31, 5567±5570. Neel, D. A.; Holmes, R. E.; Paschal,
J. W. Tetrahedron Lett. 1996, 37, 4891±4894.
11. Acheson, R. M.; Elmore, N. F. Adv. Heterocycl. Chem. 1978,
23, 263±482.
12. 6a) Dorn, H.; Otto, A. Chem. Ber. 1968, 101, 3287±3301.
Dorn, H.; Kreher, T. Heterocycles 1994, 38, 2171±2181.
13. Roussi, F.; Chauveau, A.; Bonin, M.; Micouin, L.; Husson,
H.-Ph. Synthesis 2000, 1170±1179.
È
14. Bohrisch, J.; Faltz, H.; Patzel, M.; Liebscher, J. Liebigs Ann.
1996, 1581±1585.
Ï Ï Ï
15. Svete, J.; Preseren, A.; Stanovnik, B.; Golic, L.; Golic-
Grdadolnik, S. J. Heterocycl. Chem. 1997, 34, 1323±1328.
Ï Ï
Zupancic, S.; Svete, J.; Stanovnik, B. J. Heterocycl. Chem.
1999, 36, 607±610.
16. White, J. D.; Toske, S. G. BioMed. Chem. Lett. 1993, 3, 2383±
2388.
17. Crystallographic data for the structures reported in this paper
have been deposited with the Cambridge Crystallographic
Data Center, Cambridge, UK, as a supplementary publication:
21 6CCDC 169075), 47 6CCDC 169076), 54 6CCDC 169077),
56 6CCDC 169078), 62 6CCDC 169079), 64 6CCDC 169080).
3. Pan®l, I.; Maciejewski, S.; BeøzÇecki, C.; Chmielewski, M.
Tetrahedron Lett. 1989, 30, 1522±1523. Maciejewski, S.;
Pan®l, I.; BeøzÇecki, C.; Chmielewski, M. Tetrahedron 1992,
48, 10363±10376.
4. 6a) Pan®l, I.; Chmielewski, M. Heterocycles 1993, 36, 2267±
Á
18. Frere, J.-M.; Leyh-Bouille, M.; Ghuysen, J.-M.; Nieto, M.;
Â
2273. 6b) Pan®l, I.; Krajewski, J.; Gluzinski, P.; Stefaniak, L.;
Chmielewski, M. Tetrahedron 1994, 50, 7219±7230.
Perkins, H. R. Meth. Enzymol. 1976, 45, 610±636.
19. KurzaËtkowski, W.; Solecka, J.; Filipek, J.; KurzaËtkowski,
J. D.; Kuryøowicz, W. Appl. Microbiol. Biotechnol. 1990,
33, 452±454.
Â
5. Pan®l, I.; Urbanczyk-Lipkowska, Z.; Chmielewski, M.
Carbohydr. Res. 1998, 306, 505±515.
Â
6. Frelek, J.; Pan®l, I.; Urbanczyk-Lipkowska, Z.; Chmielewski,
M. J. Org. Chem. 1999, 64, 6126±6134.
Â
20. Solecka, J.; Kurzatkowski, W. Med. Dos. Mikrobiol. 1999, 51,
151±165.