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Enhanced electron transfer between porphyrins in membranes cast on a glassy carbon electrode was observed especially in hydrophilic keratin membranes containing manganese protoporphyrin dimethyl esters (MnPPDME). An imidazole derivative played an important role on the electron transfer in hydrophobic S-cyanoethylated keratin membranes containing MnPPDME.

1,2-Bis(dihydrophytyl)glycero-3-phosphate (DPhyPA) was synthesized as an analog of archaebacterial lipids. Upon sonicating in amine-containing buffers like 0.05 M Tris–HCl (pH 7.8), the lipid gave rise to the stable liposomal assemblies, which could store 5(6)-carboxyfluorescein at high temperature as high as 70 °C in the interior. The assembly also had a large negative zeta-potential and showed an absence of gel-to-liquid crystalline phase transition from −20 to 80 °C. A Langmuir monolayer at an air/water interface suggested that the maximum molecular area of the lipid was 0.9—1.0 nm2. These properties were compared with the assemblies prepared from conventional 1,2-dipalmitoyl-sn-glycero-3-phosphate and 1,2-dipalmitoyl-sn-glycero-3-phosphocholine.

1,1′-(1,32-Dotriacontanediyl)bis[2-[(3RS,1R,11R)-3,7,11,15-tetramethylhexadecyl]-sn-glycero-3-phosphocholine] (the tetramethylhexadecyl group=phytanyl) was synthesized conveniently by reactions involving etherification of 1,1′-(1,32-dotriacontanediyl)bis(3-benzyl-sn-glycerol) (1) with (7R,11R)-3,7,11,15-tetramethyl-2-hexadecenyl bromide and hydrogenation of the resulting unsaturated ether with p-tolylsulfonylhydrazine; a total yield from 1, 7–10%. Unlike usual monopolar double-chain-amphiphiles, the bipolar lipid bent into a U-form in a water–air interface to produce the Langmuir membrane, exhibiting peculiar surface pressure–surface area isotherms.

Action of trimethyl phosphate on thymidine 5′-phosphate, deoxycytidine 5′-phosphate, deoxyadenosine 5′-phosphate, and deoxyguanosine 5′-phosphate at 37–60 °C, and pH 7–10 gave their methyl esters and base-methylated derivatives. Esterification took place in all deoxyribonucleotides to the almost same extent and its rate was enhanced by the reaction temperature, while being independent of pH in the range 7–10. On the other hand, methylation of the base moieties was affected by both the reaction temperature and pH of the reaction medium. The reactivity order of the four kinds of base moieties w s; at pH 7, cytosine base (N-3)>guanine base (N-7)>adenine base (N-1)>>thymine base (N-3); at pH 10, thymine base (N-3)>guanine base (N-1>N-7)>cytosine base (N-3)>adenine base (N-1).

2-Methoxyethoxymethyl (MEM) and 2-(trimethylsilyl)ethoxymethyl (SEM) groups were used to protect the sn-3-OH of optically active glycerols in the synthesis of 1,2-di-O-octadecyl-sn-glycero-3-phosphatidylcholine. Both MEM and SEM protective groups had advantages of a classical benzyl group by virtue of (i) the facile preparation of 1,2-O-isopropylidene-3-O-(2-methoxyethoxymethyl)-sn-glycerol and its sn-3-O-SEM analog as starting materials and (ii) the rapid demasking of the MEM and SEM moieties in lipid precursors, especially by means of titanium tetrachloride.

The quantitative determination of adenosine, guanosine, inosine, cytidine, uridine, and their methylated derivatives was studied by means of a high-performance liquid chromatographic method using ODS–silica gel cation-exchange, and anion-exchange resins as column packings. The method was apphed to the analysis of yeast-RNA, which was methylated by trimethyl phosphate at pH 7 and 9.

Uracil, thymine, cytosine, adenine, and guanine were alkylated by triethyl phosphate in a homogeneous aqueous phase at 60–80 °C, giving the corresponding ethyl derivatives in considerable yields. The reactivity order on the ethylating site in each base was found to be as follows; uracil, thymine, and cytosine: N-1>N-3; adenine: N-9≈N-3>N-7, N-1; guanine: N-1>N-7>N-3, N-9.

The synthesis of tripeptides containing aminophosphonic acid was attempted as follows. Diethyl phthalylimidomethyl phosphonate (I) was chlorinated with phosphorus pentachloride to the phosphonomonochloridate (II), which was then coupled with amino acid ethyl esters to give the corresponding dipeptides (IIIa—c). The phthalyl groups of III were removed with hydrazine, and the resulting free amines were subsequently combined with phthalyl-amino acids by means of dicyclohexylcarbodiimide to produce the tripeptide analogs (IVa—c) in good yields.

The chemical reactivity of α-aminobenzylphosphonic acid was investigated in order to survey the methods for incorporating aminophosphonic acids into a peptide chain. The investigation revealed that i) a dipeptide analog linked with a phosphonamide bond could be produced by the reaction of C-protected amino acid with the N-protected aminophosphonomonochloridate, and that ii) amino groups of the aminophosphonic acid possessed a reactivity similar to those of amino acids, and were capable of coupling with N-protected amino acids by means of dicyclohexylcarbodiimide.

Reactions of various ribonucleosides with trimethylsulfonium hydroxide were investigated in the presence of Mg2+ and Ca2+ ions. The 2′-OH groups of pyrimidine-ribonucleosides were methylated selectively.

The N-alkylation of xanthine, theophylline, and theobromine with trimethyl, triethyl, and triallyl phosphates in a weak alkaline aqueous solution is described. Especially, trimethyl phosphate converted these heterocycles to the corresponding N-methyl derivatives in good yields.

A dimer of platelet activating factor (PAF), 1,1′-(1,32-dotriacontanediyl)bis[2-acetyl-sn-glycero(3)phosphocholine] (7), was synthesized and examined for platelet aggregation and antihypertension activities. The compound 7 showed both activities with the maximum levels of 1/50–1/100-fold of those of PAF, but the antihypertension effect of 7 persisted much longer and appeared with time lag of 1–3 min. The unique expression of the activities was discussed in conjunction with the molecular structure.

Cytosine has been readily alkylated with trialkyl phosphates to give the corresponding N-alkyl derivatives, trimethyl phosphate being especially useful for the N-methylation of the base moiety of cytosine nucleosides.

Triallyl phosphate alkylated uracil (N-1), thymine (N-1), cytosine (N-1), adenine (N-3 and N-9), and guanine (presumably N-1 or N-7) in a water solution at 60 °C (pH values were 10–10.5 for uracil, thymine, cytosine, and adenine, and 12 for guanine), giving the corresponding allyl derivatives in considerable yields.

Uridine, inosine, adenosine, and thymidine were methylated selectively at the base moieties by the use of trimethyl phosphate or dimethyl sulfate in the presence of boric acid. A suppressing effect of boric acid on the methylation of the ribose-hydroxyl groups was discussed briefly.

A synthetic method for tripeptide analogs containing aminomethylphosphonic acid has been described.

Methyl, ethyl esters of phosphonic and phosphinic acids were found to be efficient alkylating agents for imidazole, benzimidazole, 1,2,4-triazole, 1,2,3-benzotriazole and pyrazole, giving the corresponding N-methyl or N-ethyl derivatives.