Synthesis of thromboxane A2 analog DL-(9,11), (11,12)-dideoxa-(9,11)-epithio-(11,12)-methylene-thromboxane A2

A synthesis of the thromboxane A₂ analog, $\text{dl}$-(9,11), (11,12)-dideoxa-(9,11)-epithio-(11,12)-methylene-thromboxane A₂ is described.     

Synthesis of thromboxane A2 analog dl-(9,11),(11,12)-dideoxa-(9,11),(11,12)-dimethylene thromboxane A2

The thromboxane A₂ analog, dl-(9,11),(11,12)-dideoxa-(9,11),(11,12)-dimethylene thromboxane A₂ (TX A₂) has been synthesized; the compound showed high agonist activities on platelet aggregation and the aorta contracting activities.     

Synthesis of thromboxane A2 analog,dl-(9,11)-methano-(11,12)-amino thromboxane A2

A synthesis of nitrogen containing thromboxane, A₂ analog, $\text{dl}$-(9,11)-methano-(11,12)-amino thromboxane A₂ ($\text{1}$) is described.     

A convenient route to (+)-(9,11)-epithia-(11,12)-methano-thromboxane A2, from prostaglandin E2, methyl ester

(+)-(9,11)-Epithia-(11,12)-methano-thromboxane A₂ which is of great importance in thromboxane research, has been synthesized from prostaglandin E₂ methyl ester.     

Synthesis of a stable analogue of thromboxane A1 (±)-9a-homo-(11,12)-deoxa-(11,12)-methylene thromboxane A1

The thromboxane A₁ (TXA₁) analogue (1) has been synthesised from the ketone (2).     

Synthesis of a stable analog of thromboxane A2 with methylene replacing the 9,11-bridging oxygen

A total synthesis of the thromboxane A₂ analog ($\text{2}$) is described.     

Synthesis of thromboxane A2 analogs—2 : (±)-Thiathromboxane A2

The total synthesis of (±)-11a-methano- 9,11-thiathromboxane A₂(1), the sulfur analog of thromboxane A₂ is described     

Synthesis of thromboxane A2 analogs—1 : (±)-Dimethanothromboxane A2

The stable thromboxane A₂ analog (±)-dimethanothromboxane A₂ 1 was synthesized from bicyclo[3.1.1]heptane 2 via the tricyclic compound 4.     

A novel stereospecific synthesis of (±)-leukotriene A4(LTA4), methyl ester

The reaction of the phosphate $\text{1}$ with the expoxyaldehyde $\text{2}$ is reported as the key step in a novel stereospecific synthesis of (±)-LTA₄, methyl ester $\text{3}$.     

Synthesis of structure analogues of thromboxane A2

Analogues I of thromboxane A₂ (TXA₂) in which the ether linkages are replaced by carbon groupings have been synthesised by elaboration of a commercially available pinene derivative IIb.     

Synthesis of 9α,11α-thiathromboxane A2 methyl ester

The synthesis of thromboxane A₂ (TXA) analogue, 9α,11α-thia-TXA₂ methyl ester $\text{2}$, in which the oxygen atom in the oxetane ring of TXA₂ was replaced by a sulfur atom, is described.     

Synthesis of thromboxane A2 analogs—3 : (+)-Thiathromboxane A2

(+)-11a-methano-9,11-thiathiromboxane A₂(1) was synthesized from prostaglandin A₂ and prostaglandin E₂.     

Synthesis of thromboxane A2 analogs—4 : (±)-Dithiathromboxane A2 sodium salt

The total synthesis of (±)-dithiathromboxane A₂ sodium salt 1 was accomplished in 26 steps from methyl 4,4-dimethoxyactoacetate.     

On the structure of thromboxane A2

The reactions of the 2-alkoxyoxetane 5 with sodium azide and methanol yield the α-azidoether 7 and the dimethyl acetal 8, respectively, paralleling reactions reported for TXA₂. The hydrolysis of 5 reported by Bruice to involve general acid catalysis proceeds at a rate similar to that reported for TXA₂. All these cleavage reactions are most likely to proceed by the same mechanism. These findings support structure 1 for TXA₂.     

Synthesis of gibberellins A8 and A56 from gibberellin A3

A mixture of gibberellin A₃ derivatives with 1(10)-ene-2,3-diol and 1(10)-ene-2,3-diol (2:5) groups, readily obtained from gibberellin A₃, has been used for a new and simple synthesis of gibberellin A₈ and its esters. The hydrolysis of GA₃ and the iodolactonization of a mixture of the 2-epimers was carried out in aqueous solution in a single flask, as also was a synthesis of GA₅₆ from GA₃ by a method that we have modified. The mixture of 1-iodides of GA₈ and GA₅₆ was separated by chromatography on SiO₂ in the form of methyl or p-bromophenacyl esters which were then deiodinated and the methyl or p-bromphenacyl ester of GA₈ was isolated. Free GA₈ was obtained by the dephenylation of the latter ester. By two-dimensional NMR spectroscopy we succeeded in assigning all the signals in the¹³C and¹H NMR spectra of the methyl esters of GA₈ and GA₅₆. In an attempt to obtain GA₅ methyl ester by the action of trimethylchlorosilane/sodium iodide on the 2,3-diol system in GA₅₆ methyl ester, the 8,13-epimer of the latter was formed, the structure of its molecule being established from the results of X-ray structural analysis.Novosibirsk Institute of Organic Chemistry, Siberian Division of the Russian Academy of Sciences. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 663–669, September–October, 1994.     

Synthesis of an electrophilic keto-tetraene 15-oxo-Lipoxin A4 methyl ester via a MIDA boronate

15-oxo-Lipoxin A₄ (15-oxo-LXA₄) has been identified as a natural metabolite of the fatty acid signaling mediator Lipoxin A₄. Herein, we report a total synthesis of the methyl ester of 15-oxo-LXA₄ to be used in investigations of potential electrophilic bioactivity of this metabolite. The methyl ester of 15-oxo-LXA₄ was synthesized in a convergent 15 step (9 steps longest linear) sequence starting from 1-octyn-3-ol and 2-deoxy-d-ribose with Sonogashira and Suzuki cross-couplings of a MIDA boronate as key steps.     

A simple synthesis of a stable thromboxane A2 analogue

A simple synthetic route, which appears to have some general utility, has been used to obtain a Bicyclo[2.2.1]heptane analogue of Thromboxane A₂.