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PETAL is an additional PW beamline to the LMJ. The kJ shots in the amplifier section, the compressor alignment and the 1.15 PW @ 850 J operations are detailed. Damage issues encountered are also addressed.

The original synthesis of combretastatin A-2 (1a) was modified to provide an efficient scale-up procedure for obtaining this antineoplastic stilbene. Subsequent conversion to a useful prodrug was accomplished by phosphorylation employing in situ formation of dibenzylchlorophosphite followed by cleavage of the benzyl ester protective groups with bromotrimethylsilane to afford the phosphoric acid intermediate 11. The latter was immediately treated with sodium methoxide to complete a practical route to the disodium phosphate prodrug (2a). The phosphoric acid precursor (11) of phosphate 2a was employed in a parallel series of reactions to produce a selection of metal and ammonium cation prodrug candidates. Each of the phosphate salts (2a-q) was evaluated with respect to relative solubility behavior, cancer cell growth inhibition and antimicrobial activity.

The (E)-stilbene isomer (2a) of the (Z)-combretastatin A-4 prodrug (1b) was efficiently prepared from (E)-combretastatin A-4 by a reaction sequence employing phosphorylation (dibenzyl chlorophosphite), cleavage (trimethyliodosilane) of the benzyl ester and reaction of the resulting phosphoric acid with sodium methoxide. The sodium phosphate product (2c) was also found to be an important side-product, presumably from iodine-catalyzed isomerization, when the analogous synthetic route was used to obtain the combretastatin A-4 prodrug (1b). The phosphoric acid precursor of prodrug 1b derived from (Z)-combretastatin A-4 (1a) was converted into a series of metal cation and ammonium cation salts to evaluate effects on human cancer cell growth, antimicrobial activities and solubility behavior.

The remarkable anticancer drug dolastatin 10 (1a) from the Indian Ocean sea hare Dolabella auricularia is currently undergoing phase I clinical trials. Thirty-eight new structural modifications of this unusual peptide have been synthesized and evaluated against a variety of human and murine cancer cell lines, and for their ability to inhibit tubulin polymerization and vinblastine and GTP binding to tubulin. Dolastatin 10 and one structural modification was found to have antifungal activity, while one other structural modification of the parent compound exhibited antibacterial activity. Some of the new peptides approximated the antineoplastic potency of dolastatin 10, especially those based on replacement of the Doe unit with Met, Phe or an appropriately substituted phenylethylamide.

New structural modifications of the marine shell-less mollusk peptide constituent dolastatin 10 (1) have been synthesized, and evaluated against a variety of cancer cell lines and for their ability to inhibit tubulin polymerization. A number of useful structure-activity relationships were uncovered. The most important observation was that the dolaphenine unit of dolastatin 10 could be satisfactorily replaced with a phenethylamine. Peptide 11C, designated auristatin PE, was found to exhibit inhibition of cancer cell growth and tubulin assembly comparable to that of dolastatin 10.