title: Rigidins B-D, new pyrrolopyrimidine alkaloids from a tunicate Cystodytes species.
abstract: Three new pyrrolopyrimidine alkaloids, rigidins B-D (1-3), have been isolated from an Okinawan marine tunicate Cystodytes sp., and the structures were elucidated on the basis of spectroscopic data.
authors.affiliation: Graduate School of Pharmaceutical Sciences, Hokkaido University, Sapporo 060-0812, Japan.
authors.forename: Masashi
authors.initials: M
authors.lastname: Tsuda
authors.forename: Kohei
authors.initials: K
authors.lastname: Nozawa
authors.forename: Kazutaka
authors.initials: K
authors.lastname: Shimbo
authors.forename: Jun'ichi
authors.initials: J
authors.lastname: Kobayashi
mesh_terms: D000470:Alkaloids / Q000737:chemistry / Q000302:isolation & purification*; D000818:Animals; D007564:Japan; D008968:Molecular Conformation; D015394:Molecular Structure; D011743:Pyrimidines / Q000737:chemistry / Q000302:isolation & purification*; D011758:Pyrroles / Q000737:chemistry / Q000302:isolation & purification*; D014561:Urochordata / Q000737:chemistry*
chemical_list: D000470:Alkaloids; D011743:Pyrimidines; D011758:Pyrroles; C475148:rigidin B; C475149:rigidin C; C475150:rigidin D