Total synthesis of Δ 12 -PGJ 2 , 15-deoxy-Δ 12,14 -PGJ 2 , and related compounds

Development of a new approach for the synthesis of (+)-15-deoxy-Δ12,14-prostaglandin J2 methyl ester based on the [2+2]-cycloadduct of 5-trimethylsilylcyclopentadiene and dichloroketene

This paper described a first example of the application of the “abnormal” lactone of 3-oxabicyclo[3.3.0]oct-6-en-2-one topology in targeted prostaglandin synthesis.

Applications of Transition-Metal-Catalyzed Asymmetric Allylic Substitution in Total Synthesis of Natural Products: An Update

Metal-catalyzed asymmetric allylic substitution (AAS) reaction is one of the most synthetically useful reactions catalyzed by metal complexes for the formation of carbon-carbon and carbon-heteroatom bonds. It comprises the substitution of allylic substrates with a wide range of nucleophiles or S_N 2'-type allylic substitution, which results in the formation of the above-mentioned bonds with high levels of enantioselective induction. AAS reaction tolerates a broad range of functional groups, thus has been successfully applied in the asymmetric synthesis of a wide range of optically pure compounds. This reaction has been extensively used in the total synthesis of several complex molecules, especially natural products. In this review, we try to highlight the applications of metal (Pd, Ir, Mo, or Cu)-catalyzed AAS reaction in the total synthesis of the biologically active natural products, as a key step, updating the subject from 2003 till date.

Enantioselective Synthesis of 15-Deoxy-Δ12,14-Prostaglandin J2

An enantioselective synthesis of 15-deoxy-Δ^12,14-prostaglandin J₂ is reported. The synthesis begins with the preparation of enantiopure 3-oxodicyclopentadiene by a lipase-mediated kinetic resolution. A three-component coupling followed by a retro-Diels-Alder reaction provides the C8 stereochemistry of the prostaglandin skeleton with high enantioselectivity. Stereoretentive olefin metathesis followed by a Pinnick oxidation affords 15-deoxy-Δ^12,14-prostaglandin J₂ in high enantiopurity.

Short Total Synthesis of Δ12-Prostaglandin J2 and Related Prostaglandins. Design, Synthesis, and Biological Evaluation of Macrocyclic Δ12-Prostaglandin J2 Analogues

Comprised of a large collection of structurally diverse molecules, the prostaglandins exhibit a wide range of biological properties. Among them are Δ¹²-prostaglandin J₂ (Δ¹²-PGJ₂) and Δ¹²-prostaglandin J₃ (Δ¹²-PGJ₃), whose unusual structural motifs and potent cytotoxicities present unique opportunities for chemical and biological investigations. Herein, we report a short olefin-metathesis-based total synthesis of Δ¹²-PGJ₂ and its application to the construction of a series of designed analogues possessing monomeric, dimeric, trimeric, and tetrameric macrocyclic lactones consisting of units of this prostaglandin. Biological evaluation of these analogues led to interesting structure-activity relationships and trends and the discovery of a number of more potent antitumor agents than their parent naturally occurring molecules.

Concise Syntheses of Δ12-Prostaglandin J Natural Products via Stereoretentive Metathesis

Δ¹²-Prostaglandin J family is recently discovered and has potent anticancer activity. Concise syntheses of four Δ¹²-prostaglandin J natural products (7-8 steps in the longest linear sequences) are reported, enabled by convergent stereoretentive cross-metathesis. Exceptional control of alkene geometry was achieved through stereoretention.

Reoptimization of the Organocatalyzed Double Aldol Domino Process to a Key Enal Intermediate and Its Application to the Total Synthesis of Δ12 -Prostaglandin J3

Re-investigation of the l-proline catalyzed double aldol cascade dimerization of succinaldehyde for the synthesis of a key bicyclic enal intermediate, pertinent in the field of stereoselective prostaglandin synthesis, is reported. The yield of this process has been more than doubled, from 14 % to a 29 % isolated yield on a multi-gram scale (32 % NMR yield), through conducting a detailed study of the reaction solvent, temperature, and concentration, as well as a catalyst screen. The synthetic utility of this enal intermediate has been further demonstrated through the total synthesis of Δ12 -prostaglandin J3 , a compound with known anti-leukemic properties.

Total synthesis of Δ¹²-prostaglandin J₃, a highly potent and selective antileukemic agent

A catalytic asymmetric total synthesis of the potent and selective antileukemic Δ(12)-prostaglandin J3 (Δ(12)-PGJ3) is described. The convergent synthesis proceeded through intermediates 2 and 3, formed enantioselectively from readily available starting materials and coupled through an aldol reaction followed by dehydration to afford stereoselectively the cyclopentenone alkylidene structural motif of the molecule.

The quest for quinine: those who won the battles and those who won the war

For a long time, the synthesis of quinine constituted an elusive target. In 2004, which marked the 60th anniversary of the publication of the approach used by Woodward and Doering to synthesize quinine, two new stereocontrolled total syntheses of the natural product were accomplished. Together with the well-publicized first stereocontrolled total synthesis of quinine by Stork in 2001, these publications evidence the revival of interest of organic chemists in the synthesis of this compound, once considered a miracle drug. The recently disclosed syntheses of quinine also testify in a remarkable manner the huge progress made by organic synthesis during the last three decades since the first series of partially controlled syntheses of quinine by the group of Uskokovic. Following an account of the historical importance of quinine as an antimalarial drug and a brief description of the experiments which contributed to its isolation and structural elucidation, the first reconstructions of quinine and the total syntheses of the natural product are discussed.