Beilstein J. Org. Chem.2017,13, 2663–2670, doi:10.3762/bjoc.13.264
analogue of streptopyrrolidine was accomplished in 65% overall yield.
Keywords: azlactones; dimerization; diasteoreselective synthesis; kinetics; streptopyrrolidine analogue; Findings
Azlactones have been acknowledged as a common nucleophilic reagent to introduce a quaternary carbon stereocenter in the α
diastereomer was assigned by X-ray analysis. Finally, one of the products was selectively reduced to provide a functionalized analogue of streptopyrrolidine, a marine natural product isolated from Streptomyces sp.
As shown in Table 1, our studies started with the synthesis of dimer 2a using azlactone 1a in the
(Scheme 3). Compound 2c was dissolved in a mixture of acetic acid and NaBH4, cooled to 0 °C to afford the highly functionalized (+/−)-streptopyrrolidine analogue 6 in 70% yield as a unique diastereomer. Streptopyrrolidine was isolated from the marine bacterium Streptomyces sp. and has exhibited a
Beilstein J. Org. Chem.2011,7, 34–39, doi:10.3762/bjoc.7.6
Debendra K. Mohapatra Barla Thirupathi Pragna P. Das Jhillu S. Yadav Division of Organic Chemistry-I, Indian Institute of Chemical Technology (CSIR), Hyderabad-500607, India, Tel/Fax: 0091-40-27193128 10.3762/bjoc.7.6 Abstract The synthesis of (4R,5R)-streptopyrrolidine (1), (4S,5R
)-streptopyrrolidine (2) (4R,5S)-streptopyrrolidine (3) and (4S,5S)-streptopyrrolidine (4) have been achieved in a concise and highly efficient manner via a highly stereoselective aldol type reaction with the trimethylsilyl enolate of ethyl acetate and Lewis acid mediated lactamization as the key reactions in ≈42
lactamization; streptopyrrolidine; Introduction
Cancer is at present the second most common cause of death, after cardiovascular diseases, and will become the primary cause in the next 10 to 20 years [1]. Traditional cancer therapies make use of chemotherapy at the maximum tolerated dose. This approach has
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Graphical Abstract
Figure 1:
Structures of (4R,5R)-streptopyrrolidine (1), (4S,5R)-streptopyrrolidine (2) (4R,5S)-streptopyrroli...