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Objective In this study we aimed to assess the feasibility and safety of fast-track surgery (FTS) combined with laparoscopy for treating patients with rectal cancer and compare the results with those of the conventional perioperative intervention group. Methods A total of 120 patients with rectal cancer were prospectively randomly assigned to the FTS combined with laparoscopy group and the conventional perioperative intervention plus laparoscopy group from November 2011 to November 2012. All patients received radical anterior resection with total mesorectal excision. Their baseline characteristics and the perioperative outcomes were recorded for analyses. Results Compared with the conventional perioperative intervention group, the fast-track protocol combined with laparoscopy could shorten the time to the first flatus (53.44 ± 23.64 h vs 67.85 ± 20.12 h, P = 0.001) and first defecation (65.23 ± 22.24 h vs 86.98 ± 24.85 h, P = 0.000) after operation, accelerate the decrease of white blood cell count (P

The photostimulated reaction of halonaphthalene with a series of carbanions derived from propionic acid derivatives in liquid ammonia led to the naphthylation at α-carbon of the carbanions in an isolated yield ranging from 25% to 86%. In all cases, the dehalonaphthalenes were found to be by-products and the reaction was inhibited by p-dinitrobenzene. An electron transfer from the carbanion to the halonaphthalene followed by ejection of halogen led to naphthyl radical, as predicted by comparing the LUMOs of the carbanions and the halonaphthalenes, was involved in the process. Absence of the alkylnaphthalene and 1,2-dinaphthylalkane in the products indicates the smooth electron transfer between (Naph-Nu)− and Naph-X. C-vs. O-naphthylation is fully addressed in terms of MNDO calculations and acid-base principle.

Direct and sensitized photolyses of 1-biphenylyl-2,2-dimethylcyclopropane gave 2-methyl-4-biphenylyl-1-butene as sole product. Comparison of the product formation quantum yields at zero conversion in direct and sensitized photolyses (1.7 × 10−3vs. 1.8 × 10−3) indicated that the rearrangement took place from the triplet excited state in both cases. A stepwise mechanism involving disrotatory ring opening of the cyclopropane and subsequent 1,3-H suprafacial shift is proposed and is consistent with the reaction multiplicity result, the orbital and state correlation diagram analyses as well as the prediction based on the Large K and Small K Concept.

The ene reactions of a-ionones with singlet oxygen were examined to ascertain the effect of secondary MO interaction between the reactants on the reaction regiospecificity. Exclusive formation of 3-hydroxy-V-ionones found in the reactions reveals favorable interaction of singlet oxygen with the acyclic fl-hydrogen atom. On the other hand, no formation of 3-hydroxy-0-ionones implies that the steric requirement was not met for the bond formation between zwitterionic perepoxide with Ci-hydrogen in the process. The MMP21 and MNDO calculations indicate minus value of the secondary interaction energy for the acyclic a-hydrogen abstraction and a repulsion between the oxygen with C1-hydrogen atom. Twisting tilting of the double bond may account for favorable attack of singlet oxygen on C3. An explanation of the excellent regiospecificity was addressed and placed in proper mechanic prospective.

The photo-SRN 1 reaction of (+)-camphor and aryl halides was investigated in order to estimate the stereochemistry of the coupling step of aryl radicals with a nucleophile. The ratio of endo to exo products determined by 1H NMR and CD spectra was found to be 99:1. MNDO calculations of the orbital parameters showed a favorable one-sided overlap of the enolate ion with the SOMO of aryl radical. In addition, fragmentation of (ArX)− was found to be related to the energy of SOMO of (ArX)−.

Dibromobiphenyl reacted with cynomethyl anion in ammonia under irradiation to form nucleophilic bis-substituted product in high yield without substantial monosubstituted product. Quantum yields far the formations of bis- and monosubstituted products were found to be 85.6 and 2.3×10−5 respectively while the corresponding pseudo-first-order rates were 6.9×10−3 and 5.2×10−10 mol·L−1·S−1. Block up the possible electron transfer of 4-brome-4′-cyanomethyl-biphenylyl radical anion to 4-cyanomethyl-biphenylyl radical and bromine ion.

A competitive coupling of amide anion over menthyl propionate anion with aryl radical in photo-SRN 1 mechanism was encountered. The reaction afforded N-aryl propionic amide in excellent yield. In contrast, the expected nucleophilic photo-SRN 1 substitution originating from the carbanion was observed in the case of t-butyl propionate. According to the proposed mechanisms and MO correlation diagrams of the coupling step of nucleophiles with aryl radical, the interesting contrast is reasonably attributed to the variation in energy gap between x*C-O and x*Ar of (ArNu)+. Usually, the odd electron of (ArNu)+ is weightly populated at x*C-O, however, the diminished privilege of x*C-O in menthyl propionate promotes a dominant population of the odd electron at x*Ar, which leads to the fragmentation of (ArNu)+ into the starting carbanion and aryl radical.