Hypolipidemic activity of N,N-dimethyl-n-octadecylamine borane in rodents

Relationship of hypolipidemic and antineoplastic activities of tricyclohexyl- and triphenylphosphine boranes, carboxyboranes, cyanoboranes, and related derivatives

A series of tricyclohexyl- and triphenylphosphine boranes, carboxyboranes and cyanoboranes were synthesized. These compounds have potent hypolipidemic effects, antineoplastic and antiinflammatory activities in rodents. Furthermore, they demonstrated potent cyctotoxicity against standard human tissue culture lines. The compounds which afforded the best hypolipidemic activity, i.e. greater than 40% reduction of serum cholesterol and triglyceride levels, were diphenyl-(4-methylphenyl)-phosphine borane and triphenylphosphine carboxyborane. Other derivatives demonstrated more potent antineoplastic activity against the Ehrlich ascites carcinoma growth including triphenylphosphine cyanoborane, 2-amino-4-methyl-pyridine cyanoborane and 2-amino-pyridine cyanoborane. Most of the derivatives showed good activity against murine L1210 lymphoid leukemia, Tmolt3 human leukemia, uterine HeLaS cells, and human glioma cell growth. Select compounds were active against colon adenocarcinoma, KB nasopharynx, lung bronchogenic and osteosarcoma cell growth. Tricyclohexyl- and triphenylphosphine boranes and the carboxy derivatives of the latter borane demonstrated good antiinflammatory activity.

Hypolipidaemic activity in rodents of boron analogs of phosphonoacetates and cyanoborane adducts of dialkyl aminomethylphosphonates

Boron analogues of phosphonoacetates proved to be potent hypolipidaemic agents in rodents, lowering both serum cholesterol and triglyceride levels. (C2H5O)3PBH2COOCH3 proved to be the most effective agent in mice, lowering serum cholesterol 46% and serum triglycerides 54% after 16 days. (C2H5O)3PBH2COOH and Na+H+(C2H5O)2(-O)PBH2COO- caused greater than a 40% reduction in lipids. The cyanoborane adducts of aminomethylphosphonates were generally less effective; (C6H5O)2P(O)CH2NH2BH2CN was the most effective, lowering serum cholesterol 32% and serum triglycerides 43% after 16 days. The phosphonoacetates appeared to lower lipid concentrations by several mechanisms. First, they lowered the de novo synthesis of cholesterol and triglycerides in the liver. Second, they accelerated the excretion of lipids into the bile and faeces. Thirdly, they modulated LDL and HDL-cholesterol contents in a manner which suggests they reduced the deposition of lipids in peripheral tissues, and accelerated the movement of cholesterol from tissues (e.g. plaques) to the liver for excretion into the bile.

Synthesis and antineoplastic activity of some cyano-, carboxy-, carbomethoxy-, and carbamoylborane adducts of heterocyclic amines

Boron analogues of piperidine, piperazine, morpholine, and imidazole proved to be cytotoxic against the growth of murine and human tissue culture cells. Significant activity was demonstrated for single-cell suspensions of L1210 lymphoid leukemia, Tmolt3 lymphoblastic leukemia, and HeLa-S3 cervical carcinoma. Trimethylamine-imidazole carbonyldihydroborane 17 demonstrated activity against solid tumor growth of human colorectal adenocarcinoma, KB nasopharynx, and osteosarcoma. In addition, 4-methylpiperidine-carbomethoxyborane 12, 2-methylimidazole-3-cyanoborane 16, and 1-methylimidazole-3-(N-ethylcarbamoyl)borane 19 were active against the KB nasopharynx growth. Piperidine-cyanoborane 2, piperidine-carboxyborane 4, and 1-methylimidazole-3-(N-ethylcarbamoyl)borane 19 were effective in reducing the growth of osteosarcoma cells. The imidazole derivatives 13-19, as well as 4-methylpiperidine-carboxyborane 11 and carbomethoxyborane 12, demonstrated good activity against lung bronchogenic and glioma growth. In the in vivo studies, N-methylmorpholine-carboxyborane 7,4-phenylpiperidine-carboxyborane 9, 4-phenylpiperidine-carbomethoxyborane 10, 4-methylpiperidine-carboxyborane 11, imidazole cyanoborane 14, and 1-methylimidazole-3-carbomethoxyborane 18 demonstrated the best activity against Lewis Lung growth and P388 lymphocytic leukemia growth in mice. Mode of action studies in L1210 leukemia cells demonstrated that piperidine-carboxyborane 4 and N-methylmorpholine-carboxyborane 7 inhibited DNA synthesis, purine synthesis at PRPP amido transferase and IMP dehydrogenase sites, and thymidine kinase and thymidine diphosphate kinase activities, while lowering d(NTP) pool levels. Also, DNA strand scission was evident after incubation with these drugs.

Acute toxicity of amine-boranes and related derivatives in mice

Three boron derivatives, i.e. trimethylamine-carbomethoxyborane, tetrakis-mu-(trimethylamine-boranecarboxylato)-bis(trimethylamine- carboxyborane)-dicopper(II), and N,N-dimethyl-n-octadecylamine borane were evaluated for acute toxicity in male mice, at 1, 2 or 5 x their therapeutic dose in rodents for pharmacological activity. Based on organ weights, clinical chemistry, hematopoietic parameters and tissue morphology, the trimethylamine-carbomethoxyborane was shown to be free of toxicity. The dicopper(II) complex and N,N-dimethyl-n-octadecylamine borane demonstrated slight toxicity with marginal disturbance in hepatic and kidney morphology. The dicopper(II) complex may cause marginal myocardial damage and the N,N-dimethyl-n-octadecylamine borane caused elevations in cholic acid. All three derivatives demonstrated reductions in hematocrit.

Synthesis and hypolipidemic activity of amine-carboxyboranes, and their amides and esters in rodents

A series of amine carboxyboranes including their amides and esters were synthesized and shown to have potent hypolipidemic activity in rodents at 20 mg/kg/day. Ethylamine carboxyborane, di-n-propylamine-carboxyborane, trimethylamine-carbomethoxyborane, n-butylamine carbomethoxyborane, methylamine-N-ethyl carbamoylborane and trimethylamine-N-n-octyl carbamoylborane were the most potent derivatives demonstrating hypocholesterolemic and hypotriglycemic activities in rats orally at 20 mg/kg/day. These derivatives lowered tissue lipids, e.g. cholesterol, in the rat liver, small intestine and aorta. The fecal lipids were elevated. Furthermore, the agents lowered cholesterol and triglycerides in the serum VLDL and LDL fractions but caused elevations in the HDL fraction after 14 days. The agents inhibited hepatic enzymatic activities of rate limiting steps involved in lipid metabolism, e.g. ATP dependent citrate lyase, sn-glycerol-3-phosphate acyltransferase and phosphatidylate phosphohydrolase.