Centella.

Total Synthesis of Terpenes and Their Biological Significance: A Critical Review

“…Under the Birch condition, the crucial reductive alkylation of enone (151) with molecule (152) went quickly and effectively, yielding the predicted coupling compound (153) in an 81% yield as the only diastereomer. Deprotection in the molecule (153) of the TBS group resulted in the production of hemiacetal (154) in a 98% yield. To directly synthesize the quinone system, hemiacetal (154) was allowed to be treated with an O 2 balloon (molecular oxygen) in acetonitrile at room temperature for 15 h in N, N -bis (salicylidene)ethylene diaminocobalt(II) (salcomine), yielding the required quinone (155) (86%).…”

“…Deprotection in the molecule (153) of the TBS group resulted in the production of hemiacetal (154) in a 98% yield. To directly synthesize the quinone system, hemiacetal (154) was allowed to be treated with an O 2 balloon (molecular oxygen) in acetonitrile at room temperature for 15 h in N, N -bis (salicylidene)ethylene diaminocobalt(II) (salcomine), yielding the required quinone (155) (86%). The formation of methoxyquinone (156) in high yield was achieved by reacting quinone (155) with five equivalents of LiN (SiMe 3 ) 2 in the presence of two equivalents of CuBr•Sme 2 in a diluted THF solution from 40 • C to r.t. for 48 h (84%).…”

“…It has been used as a cure-all since prehistoric times, but most notably for the treatment of skin diseases and dermatoses such as burns, excoriations, and hypertrophic scars [153]. Asiaticoside may promote collagen synthesis by activating the Smad pathway or inhibiting glycogen-phosphorylase [154,155].…”