Synthesis and structure verification of the vaccine adjuvant QS-7-Api. Synthetic access to homogeneous Quillaja saponaria immunostimulants.
QS-7-Api is an exceedingly potent immuno-adjuvant isolated from the bark of Quillaja saponaria. It is significantly less toxic than QS-21, a related saponin that is currently the favored adjuvant in anticancer and antiviral vaccine clinical trials. Tedious isolation/purification protocols and uncertainty in its structural constitution have hindered the clinical development of QS-7. A chemical synthesis of QS-7-Api is described, providing structural verification of the adjuvant. A novel semisynthetic sequence to QS-7-Api has also been established, greatly facilitating access to QS-7 for preclinical and clinical evaluation.
Deng
Kai
K
Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, New York 10065, USA.
Adams
Michelle M
MM
Gin
David Y
DY
D000276:Adjuvants, Immunologic / Q000138:chemical synthesis / Q000737:chemistry*; D002240:Carbohydrate Sequence; D006031:Glycosylation; D008969:Molecular Sequence Data; D009844:Oligosaccharides / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D024301:Plant Bark / Q000737:chemistry; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology; D031990:Quillaja / Q000737:chemistry*; D012503:Saponins / Q000138:chemical synthesis / Q000737:chemistry* / Q000494:pharmacology
D000276:Adjuvants, Immunologic; D009844:Oligosaccharides; D010936:Plant Extracts; C112621:QS 7; D012503:Saponins