We wish to report the synthesis of the crystalline protected nonapeptide, S-benzyl-N-tosyl-L-cysteinyl-L-tyrosyl-L-phenylalanyllglutaminyl -Lasparáginyl -Sbenzyl-L-cysteinyl-L-prolyl-N'-tosyl-L-lysylglycinamide (I),3 by the solid-phase method developed by Merrifield.4 Highly active [lysinej-vasopressin was obtained from I with excellent recovery. Recent reports about solidphase syntheses of deamino-oxytocin5 and of oxytocin6•7

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To adequately capture the market structure of vegetables in Japan, it is necessary to develop an oligopolistic model due to the potential market power of producers vs. retailers. We first estimate the market power between producers and retailers by extending the bilateral oligopoly model. Next, we evaluate the role of the wholesale market and its effect on economic welfare. Our results indicate that the wholesale market benefits both producers and consumers through a reduction in retail margins. This study contributes to the industrial organization literature by developing a bilateral oligopoly model and empirically measuring the wholesale market system in Japan.

Actinomycin D lactam has been synthesized as a potential antitumor chemotherapeutic. In this peptide analog both threonine residues of actinomycin D have been replaced by L-f/zreo-aJJ-diaminobutyric acid. The key intermediate, iV"-benzyloxycarbonyl-L-i/zreo-a,|3-diaminobutyryl-D-valyl-L-prolylsarcosyl-L-Amethylvalyl(iV0-diaminobutyric acid) lactam (VIII), was obtained by cyclization through a p-nitrophenyl ester condensation between the proline and sarcosine residues. The phenoxazinone precursor, JV-2-nitro-3-benzyIoxy-4-methylbenzoyl substituent, was introduced via its symmetrical anhydride. [l',l'-Bis(Lthreo-,ß-diaminobutyric acid)]actinomycin D exhibited five times lower toxicity and antibacterial and temporary antitumor activity in mice (Ridgway Osteogenic Sarcoma) at ca. ten times higher dose levels than actinomycin D.In a search for actinomycin analogs with improved chemotherapeutic properties, we are engaged in a program aimed at assessing the contribution of the peptide moiety to antitumor activity of the drug. Actinomycin D is used successfully, when combined with radiation therapy, in the treatment of Wilms' tumor.3 However, its usefulness for other tumors is severely restricted by its toxicity.4'5 Thus, there is strong incentive for obtaining actinomycins with broader antitumor activities and improved therapeutic indices.All natural and biosynthetic actinomycins possess two common amino acids, the threonine residue in position 1'

Die Synthese des Actinomycin‐D‐lactams (VII) gemäß dem angedeuteten Reaktionsweg wird diskutiert.