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PubMed1984

Phosphorus-nitrogen compounds. 24. Phosphoramide mustard carrier derivatives.

Diethylstilbestrol, psoralen, and propranolol were used as potential carrier molecules for selective concentrations of a nitrogen mustard moiety in breast, skin, and lung tissues, respectively. The propranolol derivative gave two racemic mixtures, which were tested to ascertain any differences in anticancer activity. The insertion of a P = O group between the carrier and oncolytic portions offsets the excess lipophilic contribution of the latter and possibly provides for latentiation of alkylating activity. Murine tumor testing of the phosphoramide mustard derivatives and two intermediates indicated that two compounds possessed marginal activity against mammary carcinoma and lymphocytic leukemia.

Animals↗
PubMed2002

Structural investigations of phosphorus-nitrogen compounds. 4. Steric and electronic effects in dibenzylamino derivatives of hexachlorocyclotriphosphazatriene and 4,4,6,6-tetrachloro-2,2-diphenylcyclotriphosphazatriene.

A systematic study is presented on the products of aminolysis of N(3)P(3)Cl(6) (1) and N(3)P(3)Ph(2)Cl(4) (4) with dibenzylamine. Two series of mono- and disubstituted derivatives of compounds (1) and (4), namely N(3)P(3)Cl(5)[N(CH(2)Ph)(2)] (2) and N(3)P(3)Cl(4)[N(CH(2)Ph)(2)](2) (3) and N(3)P(3)Ph(2)Cl(3)[N(CH(2)Ph)(2)] (5) and N(3)P(3)Ph(2)Cl(2)[N(CH(2)Ph)(2)](2) (6) [where (2), (3), (5) and (6) are new structures], are investigated in order to determine whether steric or electronic effects prevail in the formation of dibenzylamino-substituted cyclophosphazenes. The influence of an electron-releasing group (i.e. phenyl) on the stereochemistry and degree of substitution of the product is analysed by comparison of the above two series. The difference in unsymmetrically substituted endocyclic P-N bond lengths, Delta, is used as a measure of the degree of the electronic contribution, in combination with basicity constants, to quantify the degree of the electron-releasing capacity of the R group. In order to compare geminal versus non-geminal substitution, a difunctional secondary amine was used to form the compound N(3)P(3)Cl(4)[NMe(CH(2))(3)NMe] (7) (a reinvestigation) for inclusion in this study. It is shown that electron-releasing groups have a greater effect on the lengthening of P-Cl bonds as opposed to endocyclic P-N bonds and that this effect is greater in the non-geminal PRCl case than for geminal PCl(2). However, steric effects are shown to be dominant in the reactions of dibenzylamine with N(3)P(3) derivatives, with a disposition to a trans stereochemistry in bisdibenzylamino derivatives.

Journal Article↗
PubMed2002

Structural investigations of phosphorus-nitrogen compounds. 5. Relationships between molecular parameters of 2,2-diphenyl-4,6-cis-oxytetra(ethyleneoxy)-4,6-R2-cyclotriphosphazatrienes (R = Cl, OCH2CF3, OPh, OMe, NHPh, NHBut) and substituent basicity constants.

A systematic study of the products of nucleophilic substitution reactions of cis-ansa N(3)P(3)Ph(2)[O(CH(2)CH(2)O)(4)]Cl(2) (3) is reported. These reactions give a number of new structures with the general formula N(3)P(3)Ph(2)[O(CH(2)CH(2)O)(4)]R(2) [where R = OCH(2)CF(3) (4), OPh (5), OMe (6), NHPh (7 x H(2)O), NHBu(t) (8)]. A comparison has been made between the sum of the substituent basicity constants, Sigmaalpha(R), that are obtained in nitrobenzene solution and eight molecular parameters of the N(3)P(3) ring [the P-N bond lengths a, b, c; the internal bond angles alpha, beta, gamma, delta; and the difference between the bond lengths a and b, Delta(P-N)]. It is found that the systematic changes in the molecular parameters of (3)-(8) are in line with changes in alpha(R) values. This result implies the similarity in relative electron-releasing capacity of substituents R in the solid state and in solution.

Journal Article↗
PubMed2004

Structural investigations of phosphorus-nitrogen compounds. 6. Relationships between molecular parameters in per-X-substituted bridged spermine derivatives and basicity constants SigmaalphaR of substituents.

A systematic study is reported of the products of the nucleophilic substitution reactions of the spermine-bridged cyclotriphosphazene, [N3P3X4(NHCH2CH2CH2N)CH2CH2]2 [where X = Cl (2a)], to give a number of new structures [(2b)-(2g)] in which X = OPh, [spiro-O(CH2)3O]0.5, Ph, NHPh, NC4H8 and NHBut, respectively. A comparison has been made between the sum of the substituent basicity constants, Sigmaalpha(R), obtained in nitrobenzene solution, and ten molecular parameters of the N3P3 ring (the internal bond angles alpha, beta, gamma, delta and theta;, and the P-N bond lengths a, b, c, d and e) as well as the difference between the bond lengths a and b, Delta(P-N). It is found that the systematic change in molecular parameters of compounds (2a)-(2g) is in line with changes in alphaR values, indicating the similarity in relative electron-releasing capacity of substituents X in the solid state and in solution. It is also found that the effect on molecular parameters of (2a)-(2g) with two X substituents in PX2 groups is greater than that for one X substituent in P(OR)X groups in an analogous series of compounds observed previously [Besli et al. (2002). Acta Cryst. B58, 1067-1073].

Journal Article↗