Organic synthesis of 1,2-dipalmitoyl-rac-glycero-3-phosphatidylethanolamine and its effect on the induction of apoptosis in normal human lung fibroblasts.

Background /objective: The phospholipid 1,2-dipalmitoyl-rac-glycero-3-phosphatidylethanolamine (PE) comprises two fatty acid chains: glycerol, phosphate, and ethanolamine. PE participates in critical cellular processes such as apoptosis and autophagy, which places it as a target for designing new therapeutic alternatives in diseases such as pulmonary fibrosis. Therefore, this study aimed obtain PE through a six-step organic synthesis pathway and determine its biological effect on apoptosis induction in normal human lung fibroblasts (NHLF).

(23,23 ,25)-23,26-Ep-oxy-23-ethyl-furost-20(22)-en-3β-ol.

The title compound, CHO, is a steroid synthesized through a rearrangement of a sarsasapogenin derivative in acidic medium. The newly formed ring is a tetra-hydro-2-pyran heterocycle substituted by two methyl groups placed in equatorial positions. This ring displays a chair conformation, while di-hydro-furan ring , to which it is bonded, has an envelope conformation.

Azasteroids from diosgenin: Synthesis and evaluation of their antiproliferative activity.

In this work, we report the synthesis of two new azasteroids through the modification of the A and B rings of diosgenin 1. The 4-azasteroid derivative 12 was prepared in three steps using the α,β-insaturated-3-keto compound 11 as a precursor, which was first oxidized with KMnO/KIO followed by an oxidative cleavage of ring A, and subsequently cyclized with an ammonium salt, under focused microwave irradiation for a short time of 3 min. A second azasteroid was synthesized, for which the key step was the Beckmann rearrangement of ring B of the oxime 16, affording the lactam-type enamide 17 in good yield.

Diosgenin-3,6-dione: second polymorph in space group 222.

The title steroid, [(25)-spirost-4-en-3,6-dione, CHO], is obtained by oxidation of diosgenin, using the Jones reagent (CrO/HSO). The crystal structure was previously reported in space group 222, but nonetheless with the wrong absolute configuration and omitting positions for H atoms [Rajnikant (2000 ▸). , , 101-110].

Mesoscale Assembly of Bisteroidal Esters from Terephthalic Acid.

A new series of bisteroidal esters was synthesized using a spacer group, sterols and sapogenins as substrates. Steroidal dimers were prepared in high yields employing diesters of terephthalic acid as linkages at the 3β, 3'β steroidal positions. In all attempts to crystallize bisteroids, it was observed that the compounds tended to self-organize in solution, which was detected when employing various solvent systems.

Antiproliferative, Cytotoxic, and Apoptotic Activity of Steroidal Oximes in Cervicouterine Cell Lines.

Steroidal sapogenins have shown antiproliferative effects against several tumor cell lines; and their effects on human cancer cells are currently under study. Changes in the functionality on the steroidal structure make it possible to modify the biological activity of compounds. Herein, we report the synthesis and in vitro antitumor activity of two steroidal oxime compounds on cervical cancer cells.

Large-scale green chemical synthesis of adjacent quaternary chiral centers by continuous flow photodecarbonylation of aqueous suspensions of nanocrystalline ketones.

To demonstrate the ease of scale-up and synthetic potential of some organic solid state reactions, we report the synthesis, crystallization, and solid state photochemistry of acyclic, homochiral, hexasubstituted (+)-(2R,4S)-2-carbomethoxy-4-cyano-2,4-diphenyl-3-pentanone 1. We demonstrate that solid state photodecarbonylation of (+)-(2R,4S)-1 affords (+)-(2R,3R)-2-carbomethoxy-3-cyano-2,3-diphenyl-butane 2 with two adjacent stereogenic, all-carbon substituted quaternary centers, in quantitative chemical yield and 100% diastereoselectivity and enantiomeric excess. The efficient multigram photodecarbonylation of (+)-(2R,4S)-1 as a nanocrystalline suspension in water using a continuous flow photoreactor shows that the large-scale synthesis of synthetically challenging compounds using photochemical synthesis in the solid state can be executed in a remarkably simple manner.

Diosgenone: a second P2(1) polymorph.

Diosgenone [(20S,22R,25R)-spirost-4-en-3-one, C(27)H(40)O(3)] has been proposed as a new therapeutic alternative for the treatment of malaria. The first X-ray structure report for diosgenone was by Piro et al. [(2002).

Diosgenin hemihydrate.

Diosgenin [or (22R,25R)-spirost-5-en-3β-ol] is the starting material of the Marker degradation, a cheap semi-synthesis of progesterone, which has been designated as an Inter-national Historic Chemical Landmark. Thus far, a single X-ray structure for diosgenin is known, namely its dimethyl sulfoxide solvate [Zhang et al. (2005 ▶).

Stereospecific synthesis of new steroidal isoxazoles in dry media.

An easy and fast procedure was developed for one-pot synthesis of steroidal isoxazoles starting from 23-acetylsapogenins derivatives in presence of P2O5/SiO2 in dry media under microwaves irradiation is described. Substrates of the 25S and 25R series were used as raw materials, establishing that this new methodology is applicable to both series.

(R)-1-Phenyl-ethyl-ammonium trifluoro-acetate.

In the crystal structure of the title salt, C(8)H(12)N(+)·C(2)F(3)O(2) (-), all of the ammonium H atoms serve as donors for hydrogen bonds to carboxyl-ate O atoms, forming an R(4) (3)(10) ring motif based on two cations and two anions. Since both cations and anions act as inter-ion bridging groups, R(10) rings aggregate in a one-dimensional supra-molecular network by sharing the strongest N-H⋯O bond. Edge-sharing motifs lie on the twofold screw axis parallel to [010], and anti-parallel packing of these 2(1)-column structural units results in the crystal structure.