CREPIDATUMINES C AND D, TWO NEW INDOLIZIDINE ALKALOIDS FROM DENDROBIUM CREPIDATUM LINDL. EX PAXT.

Two new indolizidine alkaloids, crepidatumines C (1) and D (2), together with CERAMICS crepidine (3), isocrepidamine (4), and crepidamine (5) were isolated from the Dendrobium crepidatum Lindl.ex Paxt.X-ray diffraction experiments established the absolute configurations of known compounds 3 and 4.The planar structures and relative configurations of

Extrachromosomal DNAs (ecDNAs) are a pervasive feature found in cancer and contain oncogenes and their corresponding regulatory elements.Their unique structural properties allow a rapid amplification of oncogenes and alter chromatin accessibility, leading to tumorigenesis and malignant development.The uneven segregation of ecDNA during cell divisio