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Nitraria tangutorum Bor., having edible berries, is valued for reputed health benefits in Qinghai-Tibet plateau. The phytochemical research on the fruit juice of N. tangutorum led to the isolation of twenty-six compounds including five new compounds, tangutorids A–D ( 1 , 2 , 3a , and 3b ), and (3 E ,5 E )-7- O -β-glucosyl-4-(2-methoxy-2-oxoethyl)hepta-3,5-dienoic acid ( 15 ). The structures of these compounds were elucidated through comprehensive spectroscopic analyses. Tangutorids A–F were the first examples of glucose-derived β-carbolines from natural products. The biogenetic pathways of 1 – 8 were proposed to involve Pictet–Spengler reactions and described starting from the co-isolated tryptophan ( 10 ) and corresponding aldehydes. All isolates were evaluated for their antioxidant and α -glucosidase inhibitory activities. Compounds 21 , 22 , and 24 showed antioxidant activity with SC 50 values ranging from 12.2 ± 1.9 to 30.4 ± 2.7 μg/mL, and compound 1 showed strong α -glucosidase inhibitory effect with IC 50 value of 63.3 ± 4.6 μg/mL. [ABSTRACT FROM AUTHOR]