A new carbapenam compound No. 17927 D was obtained as the sodium salt (1) from the culture filtrates of three strains of streptomycetes isolated from soil samples and other known carbapenem antibiotics producers (e.g., Streptomyces firlvoviridis ATCC 15863). Taxonomic studies revealed the three soil isolates belong to S. firlvoviridis, named S. firlvoviridis SANK 61278, SANK 60183, and SANK 60283. Fermentation of S. firlvoviridis SANK 61278 was performed in 600-liter fermentors with a medium containing soluble starch (3.0%), soy bean meal (2.0%), Fermamine (1.0%), stearyl monoglyceride (1.0%), KH₂PO₄ (0.2%), CoCl₂·6H₂O (0.001%), and Disfoam CB-442 (0.02%) (pH 7.0 before sterilization), at 24°C for 139 hours with agitation of 220-360 rpm and aeration of 300 liters/minute. The structure of No. 17927 D was elucidated as 1 through physico-chemical properties (Table 1), ¹H NMR spectra (Fig. 1-3), and X-ray analysis of its p-nitrobenzyl ester (2) (Fig. 4), confirming the relative configuration of chiral centers as 2S, 3S, 5R, 6R, and 8R or its enantiomer. The compound exhibited no antimicrobial activity against tested Gram-positive/negative bacteria or β-lactamase inhibitory activity. Preliminary experiments suggested its potential role in the biosynthetic pathway of carbapenem antibiotics, as incubation with resting cells of S. firlvoviridis SANK 61278 increased antimicrobial activity, though the active principle was undetermined. Absolute configuration of 1 is under investigation.