A general and versatile method for the divergent and diastereoselective synthesis of polyhydroxylated indolizidines has been established. The annulation reactions of a readily available enantiopure dihydroxylated cyclic secondary enamine with alpha,beta-unsaturated carboxylates including methyl acrylate, methyl crotonate, methyl 2-hexenoate, allenoate, and dimethyl acetylenedicarboxylate and with malonyl chloride produced hexahydro- or tetrahydro-5-indolizinone-8-carboxylates in high yields. The resulting 5-indolizinone derivatives were converted into diverse polyhydroxylated indolizidines in good yields through practical hydrogenation and reduction reactions.

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The one-pot reaction of b-lactam carbenes with 1-naphthyl or 5-quinolyl isonitriles followed by treatment with aqueous hydrochloride produced benzo[h]-d-carbolin-2,4-diones or pyrido[3,2-h]-d-carbolin-2,4-diones, respectively, in moderate yields. The easy availability of b-lactam carbenes and aryl isonitriles, and the simple chemical manipulations render our approach practical in the synthesis of various novel aryl fused d-carboline derivatives, which are not easily prepared by other synthetic methods.

Ring closure reactions O 0130Solvent Controlled Divergent Syntheses of Polysubstituted Pyrroles and Pyrrolo[2,3-b]-1,4-thiazines. -The reaction of arylthiocarbamoyl imidazolium inner salts (I) with ethyl propiolate can take two different pathways depending on the polarity of the solvent. Thus, vinylthiopyrrole derivatives (III)/(IV) are predominantly formed in more polar solvents like butanone or acetone. In less polar solvents like benzene or THF, the formation of pyrrolothiazines (V) is preferred. The reaction mechanism is discussed.

Page 2214. Paragraph 2, right column, lines 4 and 5. The sentence is corrected to "The hydrogenation of 37 produced two reduction products 39A and 39B in a total yield of 74%." Page 2214. Paragraph 2, lines 13-24. Since the configurations of C-9 (the bridged carbon atom) of compounds 39A and 40 A were drawn incorrectly, the explanation of the formation of 39A should be revised as follows: "The predominant formation of 39A can be explained by a 1,4-addition-hydrogenation of 37 to form the enol 38. Isomerization of the enol forms ketones 38A and 38B, with the former being the major isomer because of less steric hindrance between the isopropylidenedioxy and ester groups. Further reduction of the ketones 38A and 38B takes place from the opposite face of isopropylidenedioxy group to give 39A and 39B, respectively."Page 2215, Scheme 5. The structures of 39A and 40 A were drawn incorrectly. The correct Scheme 5 is indicated below.Supporting Information, Pages S8 and S11. The configurations of 39A and 40A are (1S,2R,7S,8S,9R) and (1S,2R,7S,8R,9R), respectively.Supporting Information, Pages S36-S39. The wrong structures of 39A and 40A were pasted on the 1 H NMR and 13 C NMR spectra. The correct Supporting Information is included.