Carbapenem antibiotics related to thienamycin and olivanic acids, q.q.v. Carpetimycins A, B, C and D are known. Prodn of A and B by Streptomyces strain No. C-19393, now named Streptomyces griseus subsp. cryophilus, and antibacterial properties: NL 8000628; A. Imada et al., US 4518529 (1980, 1985 to Takeda); A. Imada et al., J. Antibiot. 33, 1417 (1980); by Streptomyces strain KC-6643: M. Nakayama et al., ibid. 1388. Structure and abs config: S. Harada et al., J. Antibiot. 33, 1425 (1980); M. Nakayama et al., ibid. 34, 818 (1981). Mode of action study: Y. Nozaki et al., ibid. 206. Total synthesis of (±)-carpetimycin A: H. Natsugari et al., J. Chem. Soc. Perkin Trans. 1 1983, 403; M. Ihara et al., Heterocycles 20, 2182 (1983); J. D. Buynak, M. N. Rao, J. Org. Chem. 51, 1571 (1986). Synthesis of (-)-carpetimycin A: T. Iimori et al., J. Am. Chem. Soc. 105, 1659 (1983); M. Aratani et al., Tetrahedron Lett. 26, 223 (1985); M. Shibasaki et al., ibid. 2217.