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Many alkaloids containing a tetrahydro- β-carboline skeleton have well-known therapeutic effects, leading to increased interest in the synthesis of these natural products. Enantiomers of N-Boc-protected 1-hydroxymethyl-1,2,3,4-tetrahydro- β-carboline [(±)- 7], 1-hydroxymethyl-6-methoxy-1,2,3,4-tetrahydro- β-carboline [(±)- 8], and 1-hydroxymethyl-6-fluoro-1,2,3,4-tetrahydro- β-carboline [(±)- 9] were prepared through enzymecatalyzed asymmetric acylation of their primary hydroxyl group. The preliminary experiments were performed in a continuous-flow system, while the preparative-scale resolutions were done as batch reactions. Excellent enantioselectivities ( E>200) were obtained with Candida antarctica lipase B (CAL-B) and acetic anhydride in toluene at 60 °C. The recovered alcohols and the produced esters were obtained with high enantiomeric excess values ( ee≥96 %). The O-acylated enantiomers [( S)- 10-( S)- 12)] were transformed into the corresponding amino alcohols [( S)- 7-( S)- 9)] with methanolysis. Microwave-assisted Boc removals were also performed and resulted in the corresponding compounds ( R)- 4-( R)- 6 and ( S)- 4-( S)- 6 without a drop in the enantiomeric excess values ( ee≥96 %). [ABSTRACT FROM AUTHOR]

Daily temperature measurements from six meteorological stations along the coast and fjords of western Spitsbergen have been digitized and quality controlled in a Norwegian, Russian and Polish collaboration. Complete daily data series have been reconstructed back to 1948 for all of the stations. One of the station's monthly temperature series has previously been extended back to 1898 and is included in this study. The long-term series show large temperature variability on western Spitsbergen with colder periods in the 1910s and 1960s and warmer periods in the 1930s, 1950s and in the 21st century. The most recent years are the warmest ones in the instrumental records. There is a positive and statistically significant trend in the annual times series for all of the stations; however, the strongest warming is seen in winter and spring. For the period 1979–2015, the linear trends range from 1.0 to 1.3°C/decade for the annual series and from 2.0 to 2.3°C/decade in winter. Threshold statistics demonstrate a decrease in the number of cold days per year and an increase in the number of warm days. A decreasing inter-annual variability is observed. In winter, spring and autumn, the stations in the northernmost areas of west Spitsbergen and in the innermost parts of Isfjorden are the coldest ones. In summer, however, the southernmost station is the coldest one. [ABSTRACT FROM AUTHOR]