Publications by authors named "Yong-Feng Kang"

Background: Oseltamivir resistance in influenza virus (IFV) has been of widespread concern. An increase in the frequency of viruses with reduced inhibition was observed. Whether oseltamivir is effective is uncertain.

View Article and Find Full Text PDF

Two new 1,3-benzodioxole derivatives, leucandioxoles A and B (-), together with two known related compounds (-), have been isolated from the South China Sea sponge sp. The structures of all compounds were clearly elucidated on the basis of spectroscopic analyses and compared with the literatures. The cytotoxicity against A549, Hep G2, MDA-MB-231, and HeLa cell lines of - were evaluated.

View Article and Find Full Text PDF

Three new polyhydroxysteroidal glycosides, hesperuside A (), B (), and C (), as well as a known novaeguinoside A (), were isolated from the ethanol extract of starfish collected from the South China Sea. Their structures were elucidated by extensive spectroscopic methods and chemical evidence. The compounds - present unprecedented carbohydrate chain 3--methyl-β-d-galactopyranose, which differ from each other in the side chains.

View Article and Find Full Text PDF

Three new aaptamine derivatives (1-3), together with six known related compounds (4-9), have been isolated from the South China Sea sponge Aaptos aaptos. The structures of all compounds were unambiguously elucidated on the basis of spectroscopic analyses. Compounds 1, 4, 5, 7, and 9 showed cytotoxic activities against HeLa, K562, MCF-7, and U937 cell lines with IC50 values in the range of 0.

View Article and Find Full Text PDF

Objective: To investigate the epidemiological and clinical characteristics of acute bacterial dysentery in recent years in Beijing so as to provide scientific reference for prevention and control of enteric infectious diseases.

Methods: The data of age, occupation, symptoms, signs, pathogen detection of 652 patients with acute bacterial dysentery diagnosed clinically from April 2007 to October 2007 were analyzed retrospectively.

Results: The occupations of the 652 patients included office workers and functionaries (31.

View Article and Find Full Text PDF

The catalytic asymmetric addition of phenylacetylene to aromatic ketones is reported. The catalyst, generated from commercially available Cinchona alkaloids and industrially available triethylaluminum, gives the expected tertiary alcohols with good enantiomeric excess (70-89%) and yields (60-83%). No previous case has been reported successfully using triethylaluminum as a Lewis acid in the asymmetric alkynylation of carbonylic derivatives, and thus we provide a new method to obtain optically active tertiary propargyl alcohols.

View Article and Find Full Text PDF

A PHP Error was encountered

Severity: Warning

Message: fopen(/var/lib/php/sessions/ci_session843kb0attpgivnfi1ibmpb4j76s7mlev): Failed to open stream: No space left on device

Filename: drivers/Session_files_driver.php

Line Number: 177

Backtrace:

File: /var/www/html/index.php
Line: 316
Function: require_once

A PHP Error was encountered

Severity: Warning

Message: session_start(): Failed to read session data: user (path: /var/lib/php/sessions)

Filename: Session/Session.php

Line Number: 137

Backtrace:

File: /var/www/html/index.php
Line: 316
Function: require_once