The bulbs of the Easter lily ( Lilium longiflorum Thunb.) are used as a food and medicine in several Asian cultures, and they are cultivated as an ornamental plant throughout the world. A new steroidal glycoalkaloid and two new furostanol saponins, along with two known steroidal glycosides, were isolated from the bulbs of L. longiflorum. The new steroidal glycoalkaloid was identified as (22R,25R)-spirosol-5-en-3beta-yl O-alpha-l-rhamnopyranosyl-(1-->2)-[6-O-acetyl-beta-d-glucopyranosyl-(1-->4)]-beta-d-glucopyranoside. The new furostanol saponins were identified as (25R)-26-O-(beta-d-glucopyranosyl)-furost-5-en-3beta,22alpha,26-triol 3-O-alpha-l-rhamnopyranosyl-(1-->2)-alpha-l-arabinopyranosyl-(1-->3)-beta-d-glucopyranoside and (25R)-26-O-(beta-d-glucopyranosyl)-furost-5-en-3beta,22alpha,26-triol 3-O-alpha-l-rhamnopyranosyl-(1-->2)-alpha-l-xylopyranosyl-(1-->3)-beta-d-glucopyranoside. The previously known steroidal glycosides, (22R,25R)-spirosol-5-en-3beta-yl O-alpha-l-rhamnopyranosyl-(1-->2)-beta-d-glucopyranosyl-(1-->4)-beta-d-glucopyranoside and (25R)-26-O-(beta-d-glucopyranosyl)-furost-5-en-3beta,22alpha,26-triol 3-O-alpha-l-rhamnopyranosyl-(1-->2)-beta-d-glucopyranosyl-(1-->4)-beta-d-glucopyranoside were identified in L. longiflorum for the first time. These new compounds from L. longiflorum and the isolation methodologies employed can be used for studies on the biological role of steroidal glycosides in plant development and plant-pathogen interactions, as well as for studies in food and human health, for which little is known.

Bromo and chloro substituents serve as excellent blocking groups on aromatic rings. When a halo substituent is para to an ortho,para-directing group, the ortho positions can be easily functionalized, and the halo group can be subsequently removed by catalytic hydrogenation under neutral conditions. As expected, bromides are reduced more quickly than chlorides and the reaction requires the use of less catalyst. Bromides can be selectively reduced in the presence of nitro, chloro, cyano, keto, or carboxylic acid groups.

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