Abstract
An appropriately substituted α-diazo β-keto
ester, prepared from d -glucose, on treatment
with a catalytic amount of dirhodium tetraacetate gave a strained
1,5-dioxabicyclo[3.3.0]octane ring system with
concomitant diastereoselective formation of a quaternary carbon
substituted with both an ethoxycarbonyl group and a 2-ethoxy-2-oxoethyl
group; the product is a key intermediate in the synthesis of a new
griseolic acid analogue.
Key words
carbenoids - carbohydrates - carboxylic acids - diazo compounds - oxygen heterocycles
References
1 Nakagawa F.
Okazaki T.
Naito A.
Iijima Y.
Yamazaki M.
J.
Antibiot.
1985,
38:
825
2a Murofushi Y.
Kimura M.
Kuwano H.
Iijima Y.
Yamazaki M.
Kaneko M.
Chem.
Pharm. Bull.
1988,
36:
3760
2b Miyakoshi S.
Haruyama H.
Shioiri T.
Takahashi S.
Torikata A.
Yamazaki M.
J. Antibiot.
1992,
45:
395
2c Kaneko M.
Kimura M.
Murofushi Y.
Yasumoto T.
Iijima Y.
Yamazaki M.
Nucleosides Nucleotides
1992,
11:
865
3a Pickering L.
Nair V.
Nucleosides
Nucleotides
1996,
15:
1751
3b Pickering L.
Nair V.
Nucleosides Nucleotides
1997,
16:
1435
4a Iijima Y.
Nakagawa F.
Handa S.
Oda T.
Naito A.
Yamezaki M.
FEBS Lett.
1985,
192:
179
4b Murofushi Y.
Kimura M.
Iijima Y.
Yamazaki M.
Kaneko M.
Chem.
Pharm. Bull.
1987,
35:
1036
4c Murofushi Y.
Kimura M.
Kuwano H.
Iijima Y.
Mitsuo Y.
Kaneka M.
Nucleic Acids Symp. Ser.
1986,
17:
45
4d Murofushi Y.
Kimura M.
Iijima Y.
Yamazaki M.
Kaneka M.
Chem. Pharm.
Bull.
1987,
35:
4442
4e Murofushi Y.
Kimura M.
Iijima Y.
Yamazaki M.
Kaneka M.
Chem.
Pharm. Bull.
1988,
36:
1309
5a Tulshian D.
Doll RJ.
Stansberry MF.
McPhail AT.
J. Org. Chem.
1991,
56:
6819
5b Tulshian D.
Czarniecki M.
Doll RJ.
Ahn HS.
J. Med. Chem.
1993,
36:
1210
5c Tulshian D.
Czarniecki M.
J. Am. Chem. Soc.
1995,
117:
7009
6 Knapp S.
Madduru MR.
Lu Z.
Morriello GJ.
Emge TJ.
Doss GA.
Org.
Lett.
2001,
3:
3583
7a Dhavale DD.
Desai VN.
Saha NN.
J.
Chem. Soc., Perkin Trans. 1
,
7b Dhavale DD.
Karche NP.
Jachak SM.
J. Org. Chem.
2001,
66:
6323
7c Adams J.
Spero DM.
Tetrahedron
1991,
47:
1765
7d Padwa A.
Krumpe KE.
Tetrahedron
1992,
48:
5385
7e Ye T.
McKervey MA.
Chem. Rev.
1994,
94:
1091
7f Padwa A.
Weingarten MD.
Chem. Rev.
1996,
96:
223
7g Doyle MP.
Forbes DC.
Chem.
Rev.
1998,
98:
911
7h Sulikowski GA.
Cha KL.
Sulikowski MM.
Tetrahedron: Asymmetry
1998,
9:
3145
7i Doyle MP.
Acc. Chem. Res.
1986,
19:
348
7j Pirrung MC.
Morehead AT.
J.
Am. Chem. Soc.
1994,
116:
8991
7k Taber DF.
Green JH.
Zhang W.
Song R.
J. Org. Chem.
2000,
65:
5436
8 Karche NP.
Jachak SM.
Dhavale DD.
J. Org. Chem.
2003,
68:
4531
9 Slessor KN.
Tracey AS.
Can. J. Chem.
1969,
47:
3989
2 into gulose derivative 3a by the
reported procedures gave a low yield (17%). Various literature
methods were attempted:
10a reduction with NaBH4 resulted
in the isolation of 15% of gulose 3b ;
10b reaction of 2 with NaBH3 CN led to the recovery
of the starting compound; and
10c diimide reduction afforded
an inseparable mixture of products. See ref. 9.
11 Selective hydrolysis of the 5,6-O -isopropylidene group in 3c was
possible probably because of the α-orientation of the 5,6-diol
in the furanose ring; transfer of a proton from the protonated oxygen
at the C-6 carbon to the C-1 acetonide facilitates the 1,2-acetonide
deprotection competitively. Attempts with various other acidic reagents,
such as 10% H2 SO4 , CuCl2 ˙2H2 O,
30% HClO4 , or acidic resin (Indion 140), failed
to give good yields.
12a Dhavale D.
Bhujbal N.
Joshi P.
Desai S.
Carbohydr. Res.
1994,
263:
303
12b The ¹ H
and ¹³ C NMR spectra of 5 showed
additional signals (<10%) due to the presence
of the enol form.
13 The unstable nature of compound 7 precluded further characterization. At
this stage, attempts were made to convert the keto compound 7 into one with an olefinic functionality
at the ring junction. Thus, attempts at the reaction of 7 by using the Shapiro protocol (SO2 Cl2 and POCl3 )
led to a complex mixture. Attempts to activate the hydroxyl functionality
by using mesyl chloride and subsequent treatment with base under
reflux were also unsuccessful.
14 Our attempts to isolate the other
diastereomer (C-5β-OH) in a pure form were unsuccessful.
15 In the ¹ H NMR
spectrum of 9 , the C-5 appeared at δ = 5.
5 as a doublet (J
5,4 = 5.00
Hz). In 1D NOSEY irradiation, one of the C-7 methylene protons at δ = 2.48
showed a NOE with H-3, H-4, H-5, indicating a syn -relationship
between the 2 COOEt group and the
sugar ring protons, and confirming our earlier assignment.
16 The ¹ H NMR spectrum
of 10 shows the presence of an anomeric
mixture in the ratio 1:15 in favor of the β-anomer.
17a Vorbrüggen H.
Krolikiewicz K.
Bennua B.
Chem. Ber.
1981,
114:
1234
17b Vorbrüggen H.
Ruh-Polenz C.
Org.
React.
2000,
55:
1
