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The synthesis and characterization of two novel diastereomeric Mannich bases was carried out from the reaction of the cyclic aminal (2R,7R,11S,16S)-1,8,10,17-tetraazapentacyclo[8.8.1.1.8,170.2,70.11,16]icosane 1 and p-cresol 2a and 4-methoxyphenol 2b in a water/dioxane mixture. The title compounds (4a–b) are interesting because bearing two 3-(2-hydroxy-5-substitutedbenzyl)octahydro-1H-benzimidazol-1-yl]methyl} substituents joined to an arenol ring. The formation of these new Mannich bases in the reaction mixture can be explained by aminomethylation of previously reported di-Mannich base 2,2′-((hexahydro-1H-benzo[d]imidazole-1,3(2H)-diyl)bis(methylene))bis(4-substituentphenol) 3a–b. NMR analysis demonstrated that compounds 4a–b were formed as diastereomeric mixtures. Subsequent experiments revealed that at longer reaction times, the percentage yield of these new products increased considerably (yield percentages up to 22–27%), suggesting a nucleophilic competition between the p-substituted phenols and Mannich bases of type 3 for aminal 1. [ABSTRACT FROM AUTHOR]

International service-learning combines aspects of conventional study abroad with aspects of conventional service-learning, offering an exceptional degree of integration into a target culture and an intensive experience of community service. The present study describes an effort to establish, through qualitative assessment, the degree to which such integration and experience actually take place, and their effects on the students involved. The authors focus on the first of three Ford Foundation-funded studies that are assessing the impact of the International Partnership for Service-Learning and Leadership on its three separate constituencies: (1) the students participating in Partnership programs; (2) the in-country agencies that sponsor the students; and (3) the in-country universities that house Partnership programs. The authors describe the first study, qualitative in nature, which sought to document the impact of the Partnership on student goals and attitudes through conducting interviews and focus groups with seventeen former participants. The study sought to explore two assumptions about student learning. The first is that study abroad provides students with rich environmental opportunities that allow them to interact and learn in ways not often available on their home campuses. The second is specific to the Partnership's own programs: that service-learning provides special opportunities for cultural integration, and that such experience broadens students' horizons and prepares them to be global citizens. The authors discuss what the students had to say about some of the major components of the international service-learning experience and end with a discussion of what the study revealed about ways to improve that experience. (Contains 6 notes.)

Zanthoxylum simulans Hance, commonly known as Sichuan pepper, is a well-known medicinal plant recognized for its potential as a source of bioactive specialized metabolites. As part of our interest in natural antifungal compounds, the present study describes the discovery of an unreported N-alcoxycarbonylbenzo[c]phenanthridinium salt, N-methoxycarbonyl-9,12-dimethoxy-norchelerythrine 1 (a type-III benzo[c]phenanthridine), isolated from Z. simulans seedlings, which were propagated under controlled greenhouse conditions. Six-month seedlings were harvested and subjected to cold acid–base extraction. Chromatographic techniques achieved the isolation of 1 from raw alkaloid extract. The structural elucidation of 1 was accomplished through comprehensive spectroscopic analysis, including nuclear magnetic resonance and high-resolution mass spectrometry. Fusarium oxysporum, a fungal pathogen responsible for substantial agricultural losses, was exposed to different concentrations of the novel compound, exhibiting potent antifungal efficacy (IC50 < 3 µM) and fungicide effects. These findings highlight the potential of benzophenanthridines as antifungal leads and underscore the importance of exploring natural products for agricultural applications. [ABSTRACT FROM AUTHOR]