Stereochemical insights into enantioselective antiplasmodial lignanamides from the twigs and leaves of Solanum erianthum.

Stereochemical investigations on the twigs and leaves of Solanum erianthum afforded five pairs of lignanamide enantiomers and a previously undescribed phenolic amide (3). Particularly, two pairs of previously undescribed lignanamide racemates (1a/1b-2a/2b) represent the first case of natural products that feature an unreported 5/5-fused N/O-biheterocyclic core. Their structures, including the absolute configurations, were determined unambiguously by using spectroscopic analyses and electronic circular dichroism calculations. A speculative biogenetic pathway for 1-3 was proposed. Interestingly, these lignanamides exhibited enantioselective antiplasmodial activities against drug-sensitive Plasmodium falciparum 3D7 strain and chloroquine-resistant Plasmodium falciparum Dd2 strain, pointing out that chirality plays an important role in drug development.

Sesquiterpenoids and Cytochalasins with Immunosuppressive Activity from Sonchus wightianus.

The plant species, Sonchus wightianus DC., was historically used in China for both medicinal and dietary uses. In present study, seven new guaiane sesquiterpenoids (1-7) and one cytochalasin (8), along with five known guaianes (9-13) and two known cytochalasins (14 and 15), were isolated from the whole plants of S. wightianus. These guaianes showed structural variations in the substituents at C-8 and/or C-15, and compounds 6 and 7 are two sesquiterpenoid glycoside derivatives. Their structures were determined by extensive analysis of spectroscopic, electronic circular dichroism, and X-ray diffraction data, and chemical method. Biological tests revealed that compounds 5 and 8 are potent and selective immunosuppressive reagents.

[Review of Research on the Impacts of Atmospheric Pollution on the Health of Residents].

With the rapid development of the economy, the atmospheric pollution in China has become very severe, and poses a great threat to human health. On the basis of relevant research achievements at home and abroad, this paper summarizes the impact of atmospheric pollution on the health of residents from the two aspects of research content and method. It was found that current research is mainly focused on calculating the health losses, evaluating the economic cost of health losses, and analyzing the health benefits of controlling atmospheric pollutants at the macro level, while studies at the micro level are relatively scarce. Moreover, current studies at the micro individual level is mostly empirical research related to epidemic cases abroad; however, domestic research at the micro individual level is still at the initial stage of qualitative analysis. In addition, the quantitative assessment method of atmospheric pollution on the health of residents is also improving. Apart from methods in common use (meta-analysis, Poisson regression model, human capital method, willingness to pay method and disease cost method), there are other methods that are widely used (input-output model and computable general equilibrium model). In general, the effects of atmospheric pollution on resident health include both chronic and short-term acute effects, and involve many other factors as well, such as socioeconomics, natural conditions, behavioral preferences, and personal physiology. Although the depth and breadth of the research are expanding, and the level of discipline integration is being continuously improved, it is necessary to strengthen domestic epidemiological studies, to pay attention to the integration of macro (regions) and micro (individuals), to focus on the reduction and distribution of atmospheric pollutants from a health perspective, and to attach importance to the construction of a basic database in the future to provide a scientific basis for establishing a systematic framework for the analysis of the effects of atmospheric pollution on the health of residents.

Structural Elucidation and Total Synthesis of Three 9-Norlignans from Curculigo capitulata.

Capitulactones A-C, three unprecedented 9-norlignans featuring a unique 3,5-dihydrofuro[2,3- d]oxepin-7(2 H)-one scaffold, were isolated from the roots of Curculigo capitulata. Their structures with absolute configurations were unambiguously established by a combination of spectroscopic data, ECD analysis, and total synthesis. Biomimetic total syntheses of three pairs of the corresponding enantiomers were achieved in 9-10 steps with overall yields of 14.8, 12.7, and 10.3%, respectively. Notably, the unique scaffold of the common western hemisphere of the molecules was constructed by using the oxidation-reduction strategy from benzodihydrofuran.

Effect of Zhenwu Tang Granule on pressure-overloaded left ventricular myocardial hypertrophy in rats.

BACKGROUND: In the perspective of traditional Chinese medicine, few studies have focused on the compound preparations though there are many investigations. The present study was undertaken to investigate the effect of Zhenwu Tang Granule on chronic pressure-overloaded left ventricular hypertrophy in rats. METHODS: The study was performed at the laboratory of Guangzhou Institute of Respiratory Disease. Male SD rats were divided randomly into 3 groups: sham operation group (n=8), operation group (n=15) and traditional Chinese medicine (TCM) group (n=15). The model of myocardial hypertrophy was made by gradually constricting the abdominal aorta. Sixteen weeks later, cardiac ultrasonography was performed in all groups in order to ascertain post-operational left ventricular (LV) hypertrophy. And Zhenwu Tang Granule was added at a dose of 12 g/kg in the mixed feedstuff for 8 weeks in the TCM group. In the 24th week, weight, structure as well as function of the heart in each group were measured by high-frequency ultrasonography, and Masson's staining was performed on the cardiac muscles. Meanwhile, total collagen volume fraction (CVF-T) and non-coronary vessel collagen volume fraction (CVF-NV) were analyzed. RESULTS: There was an increase in the weight of the heart in the operation group, with the left ventricule dominated (P<0.05). The heart was enlarged, with diastolic interventricular septal distance (IVSd) and left ventricular posterior wall distance (LVPWd) dominated (P<0.01). There was a significant decrease in the cardiac function (P<0.05). The weight (P<0.01) and volume of the heart decreased in the TCM group compared with the operation group, with IVSd and systolic left ventricular posterior wall dominated (P<0.01). And the cardiac function was improved (P<0.05). Significant interstitial and collagen hyperplasia was shown in the operation group based on pathological analysis, and various improvements were proved in the TCM group, i.e. there was a significant decrease in CVF-T and CVF-NV (P<0.01) compared with the operation group; but no difference (P>0.05) was found when compared with the pseudo-operation group. CONCLUSION: Zhenwu Tang Granule could reduce the weight and volume of the heart, improve the cardiac function, inhibit hyperplasia of collagen, and reverse myocardial hypertrophy in rats with pressure-overloaded left ventricular hypertrophy.

Exploring an expedient IMDA reaction approach to construct the guanacastepene core.

Construction of the [5-7-6] tricyclic core of guanacastepenes was attempted by using the intramolecular Diels-Alder (IMDA) reaction and Me(3)Al-mediated ring opening of the oxabridge as key synthetic steps. The illustrated chemistry demonstrated a synthetic feasibility to build up the framework of guanacastepenes by the IMDA reaction. [reaction: see text]

Total synthesis of wedelolactone.

The total synthesis of wedelolactone, a naturally occurring direct inhibitor of IKK complex that can suppress LPS-induced caspase-11 expression, using a convergent synthetic approach, is described. The key steps involved in this synthesis include the palladium-catalyzed Sonogashira reaction and the palladium-catalyzed carbonylative annulation reaction. This approach allows access to diversified analogues of wedelolactone.