The photochemical decarboxylation of acyl hypoiodites has been investigated and shown to provide an efficient method for the preparation of the corresponding nor-iodides. Primary and secondary carboxylic acids are readily decarboxylated by using the lead tetra-acetate-iodine reagent. The recently discovered t-butyl hypoiodite has been shown to form acyl hypoiodites at room temperature. With this reagent primary, secondary, and tertiary acids, as well as the hitherto intractable glutaric and adipic acids, can be decarboxylated without difficulty.Some aspects of our work have already been reported in preliminary form.1 THE Hunsdiecker method for the decarboxylation of acids is well It suffers from certain disadvantages amongst which the difficulty and expense of preparing dry silver salts may be mentioned. Recently Cristol et aL3 introduced a modified Hunsdiecker procedure, using mercuric salts, which has certain advantages. At the initiation of our own worktye argued that if acyl hypoiodites could be prepared conveniently they might well be induced to decompose photochemically at relatively low temperatures into iodide and carbon dioxide. The important discovery of Wettstein and his collaborators that the hypoiodites from alcohols can be prepared advantageously by the in situ interaction of lead tetraacetate, alcohol, and iodine suggested that acyl hypoiodites might be obtained similarly.6 Our experiments soon provided evidence that this was correct and that in many cases decarboxylation proceeded smoothly on illumination with a tungsten lamp. All the * Part XVI, J., 1964, 2518.

Multidrug resistance (MDR) mediated by P-glycoprotein (Pgp) remains the major obstacle for successful treatment of cancer. Inhibition of Pgp transport is important for higher efficacy of anticancer drugs. Lipophilic cationogenic amines with at least one tertiary N atom, such as verapamil, are classical PgP-blocking agents. In a search for novel accessible compounds potent against MDR tumor cells, we synthesized a series of arylalkylamines that contain isoprenoid side chains of different length. Two out of seven new analogues of the known N,N'-bis(3,4-dimethoxybenzyl)-N-solanesylethylenediamine (SDB-ethylenediamine), namely, compounds with C10 and C15 side chains, at low micromolar concentrations were preferentially toxic for several mammalian tumor cell lines that acquired MDR during prolonged drug selection. Moreover, at noncytotoxic concentrations, these compounds potently sensitized MDR cells to Pgp substrates vinblastine and adriamycin. We conclude that these analogues of SDB-ethylenediamine may have dual therapeutic advantage because (i) they are preferentially toxic for MDR cells when administered alone and (ii) they potentiate the cytotoxicity of Pgp-transported anticancer drugs.

+)-j-Citronellene, the main component of the %ecbnical grade pyrolysate of (+)-cis-pinane, can be chemoselectively processed to certain C10 derivatives in the presence of isomeric Clo olefins. These derivatives are converted into mono-and bifunctional chiral building blocks suitable for the incorporation of4deCH.Y fragments with 8-or &con-figuration into aliphatic chains. Although their optical purity may be as low as 50%, that o f the end prQducts can be upgraded by inclusion of an optical resolution step in the synthetic sequence.

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We report the observation of changes in the wave turbulence properties of gravitycapillary surface waves due to a finite-depth effect. When the fluid depth is decreased, a hump is observed on the wave spectrum in the capillary regime at a scale that depends on the depth. The possible origin of this hump is discussed. In the gravity regime, the wave spectrum still shows a power law but with an exponent that strongly depends on the depth. A change in the scaling of the gravity spectrum with the mean injected power is also reported. Finally, the probability density function of the wave amplitude rescaled by its rms value is found to be independent of the fluid depth and to be well described by a Tayfun distribution.