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There is increasing evidence of long non-coding RNA (lncRNA) involvement in a variety of biological responses to environmental stresses. The toxic heavy metal cadmium (Cd) is one of the major inorganic contaminants in environments. How lncRNAs are involved in Cd stress-induced response and regulatory mechanism in dicot plants is unknown. The present study performed strand-specific RNA-sequencing (RNA-Seq) to profile lncRNAs in Cd-exposed rapeseed (Brassica napus). More than 60 million clean reads corresponding to 5038 unique B. napus lncRNAs were identified, in which 2546 lncRNAs were generated from the sense strand and 2492 were generated from natural antisense transcripts (lncNATs). A combinational analysis resulted in identification of 301 lncRNAs responding to Cd stress. Cd-induced expression of lncRNAs appeared to be associated with their nearby protein-coding genes. Many coding genes flanking lncRNA loci were involved in Cd uptake, translocation and stress-responses, suggesting that the associated lncRNAs might have similar functions. Four lncRNAs were identified as precursors of miR824, miR167d, miR156d and miR156e. Sixty-seven lncRNAs acted as competing endogenous target mimics (eTMs) for 36 miRNAs potentially involved in Cd stress response. The functional mimics were validated by transient transformation of three lncRNAs into B. napus protoplasts under control of double 35S promoter with a decoy lncRNA (d35S-lncRNAs-pAN580). These results suggest that a set of putative lncRNAs were involved in response to Cd stress in B. napus.

We report the first one-pot reductive homocoupling reaction of secondary amides and cross-coupling reaction of secondary amides with ketones to give secondary vicinal diamines and amino alcohols. This method relies on the direct generation of α-amino carbon radicals from secondary amides by activation with trifluoromethanesulfonic anhydride, partial reduction with triethylsilane and samarium diiodide-mediated single-electron transfer. The reactions were run under mild conditions and tolerated several functional groups.

National Basic Research Program (973 Program) of China [2010CB833200]; National Natural Science Foundation of China [20832005]; Natural Science Foundation of Fujian Province of China [2011J01054]

National Natural Science Foundation of China[20832005]; National Basic Research Program (973 Program) of China[2010CB833200]

The title compound, C29H35N3O4, was obtained by the reaction of (2S,4S,5S)-tert-butyl N-(4-amino-1-benzyl-3-hydroxy-5-phenylpentyl)carbamate and picolinic acid using oxalyl chloride as a chlorinating reagent to activate the carboxyl group. In the crystal structure there are two molecules in the asymmetric unit, which are aligned edge-to-face. In one molecule, the pyridyl ring forms a dihedral angle of 22.0 (1)° with the phenyl ring of the terminal benzyl group and 14.3 (1)° with the other phenyl ring; in the other molecule, the corresponding angles are 12.1 (1) and 10.6 (1)°, respectively. The packing is stabilized by intermolecular hydrogen bonds and C—H...π interactions.

The title compound, C21H26N2O, was obtained as an unexpected by-product when attempting to prepare (S)-2-benzyl-N-tert-butyl-1,2,3,4-tetrahydroisoquinoline-3-carboxamide from (S)-2-benzylamino-N-tert-butyl-3-phenylpropanamide and dimethoxymethane. The molecules are linked by weak C—H...O hydrogen bonds, generating linear chains parallel to the b axis. C—H...π interactions provide further stability for the crystal structure. The planes of the two phenyl rings make a dihedral angle of 84.1 (1)°. The absolute configuration was known from the starting material.

Amides are widely used as stable synthetic intermediates in organic synthesis and medicinal chemistry. Versatile and chemoselective C—C bond forming methods for the direct transformation of amides are highly demand- ing. In this paper, we report the reductive cycloaddition of common secondary amides with the Danishefsky diene to produce 2-substituted 2,3-dihydro-4-pyridones. This one-pot procedure involves amide activation with triflic anhy- dride, partial reduction, and (4+2) cycloaddition. The synthetic utility of this step-econimical method was demon- strated by the short and protecting-group-free total syntheses of alkaloids (±)-lasubine I and (±)-myrtine.

The title compound, C31H31N3O, was obtained by the reaction of 4-dibenzyl­amino-3-oxo-5-phenyl­penta­nenitrile with 2-methyl­pyridinylmagnesium chloride. The crystal structure involves inter­molecular N—H⋯O hydrogen bonds.

The crystal structure of the title compound, C9H13NO3, is stabilized by inter­molecular O—H⋯O and N—H⋯O hydrogen bonds, leading to a two-dimensional network extending parallel to the (001) plane. The absolute configuration has been assigned by reference to the chiral hydr­oxy C atom, which remains unchanged during the synthetic procedure.

The title compound, C25H27NO3S, was obtained as the major product from the reaction of (3S,4S)-4-(dibenzyl­amino)-5-phenyl­pentane-1,3-diol and sulfuryl dichloride. The mol­ecular packing in the crystal is stabilized by weak inter­molecular inter­actions and van der Waals forces.

The title compound, C29H35NO3, was obtained as a major product by reduction of (S)-tert-butyl 4-dibenzyl­amino-3-oxo-5-phenyl­penta­noate. The mol­ecular packing in the crystal structure is stabilized by weak inter­molecular inter­actions and van der Waals forces.

The title compound, C19H27NO3, was obtained by the reaction of (3S,7aR)-7a-hexyl-7-methoxy-3-phenyl-2,3-dihydropyrrolo[2,1-b]oxazol-5(7aH)-one and triethylsilane using titanium(IV) chloride as catalyst. In the molecule, the phenyl and dihydropyrrolone rings form a dihedral angle of 83.8 (1)°. O—H...O hydrogen-bonding interactions lead to the formation of a chain parallel to the a axis.

In the title chiral butterfly-like bicyclic lactam, C(14)H(15)NO(3), the phenyl and methyl groups are syn with respect to each other. The dihydro-pyrrrole ring adopts a boat conformation, whereas the oxazole ring has a slightly distorted boat conformation. The packing of mol-ecules in the crystal structure is stabilized by inter-molecular C-H⋯O hydrogen bonds.

The title compound, C22H23NO3, was obtained by the reaction of (2R,3R)-N-benzhydryl-N-(2-cyclo­propyl-2-oxoeth­yl)-2,3-epoxy­butyramide with Lithium bis(trimethylsilyl)amide in tetra­hydro­furan solution. The absolute configuration has been assigned by reference to an unchanging chiral centre in the synthetic procedure. The mol­ecular packing is stabilized by inter­molecular O—H⋯O and C—H⋯O hydrogen bonds.