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Inspired by the chemistry and biology of butyrolactones, pyrrolidines, and chromanones, we successfully developed a simple domino 1,3-dipolar cycloaddition of homoserine-lactone-derived azomethine ylides for the construction of biologically important spiro[butyrolactone–pyrrolidine–chromanone] hybrids in the presence of Et3 N as a catalyst under mild conditions. The reaction is based on the application of carboxylic-acid-activated chromones as dienophiles, followed by a decarboxylation process. This reaction displayed good substrate tolerance and gave the desired products in moderate to good yields with high diastereoselectivities (up to 85% yield and >20:1 diastereomeric ratio) via an exo -transition state. This is the first example of an introduction of a chromanone moiety into a spiro[butyrolactone-pyrrolidine] framework, which might be valuable in medicinal chemistry. [ABSTRACT FROM AUTHOR]

A novel halophilic actinobacterium, designated strain TRM 49201T, was isolated from a hypersaline soil in Xinjiang Province, north-west China. The strain was aerobic, Gram-stain-positive and halophilic. The aerial mycelium was chaotic with irregular branches, and spherical sporangia containing several spherical spores developed at mycelial aggregations. The strain had an optimum NaCl concentration for growth of 8-13 % (w/v). The whole-cell sugar pattern of strain TRM 49201T consisted of xylose and ribose. The predominant menaquinones were MK-9(H4), MK-9(H6) and MK-10(H2). The polar lipids were diphosphatidylglycerol, phosphatidylinositol mannoside, phosphatidylinositol, phosphatidylglycerol, phosphatidylcholine and four unknown phospholipids. The major fatty acids were anteiso-C15 : 0, iso-C16 : 0 and anteiso-C17 : 0. The G+C content of the genomic DNA was 70 mol%. Phylogenetic analysis showed that strain TRM 49201T can be distinguished from representatives of Glycomyces, Stackebrandtia and Haloglycomyces, the three existing genera in the family Glycomycetaceae, based on low 16S rRNA gene sequence similarities ( < 94.42 %). Strain TRM 49201T is thus considered to represent a novel species of a new genus in the family Glycomycetaceae, for which the name Paraglycomyces xinjiangensis gen. nov., sp. nov. is proposed. The type strain of Paraglycomyces xinjiangensis is TRM 49201T ( = NRRL B-24926T = CCTCC AA 2013002T = KACC 17683T).