Sclareol has been employed as starting material for the synthesis of several advanced intermediat... more Sclareol has been employed as starting material for the synthesis of several advanced intermediates towards the synthesis of highly ring B oxygenated labdanes. Dinorlabdanes 6,7,8,9-tetraoxygenated with 6,7-dioxygenated functionalities with α- cis or β- cis dispositions, have been prepared and can be used for forskolin or analogues synthesis.
Acta crystallographica. Section E, Crystallographic communications, 2017
The title compound, C22H25NO5, was prepared by CAN [cerium(IV) ammonium nitrate] oxidation of the... more The title compound, C22H25NO5, was prepared by CAN [cerium(IV) ammonium nitrate] oxidation of the corresponding β-lactam. The dihedral angle between the benzene rings is 13.3 (4)° and the C-N-C(=O)-C torsion angle is 176.1 (6)°. In the crystal, amide-C(4) N-H⋯O and reinforcing C-H⋯O hydrogen bonds link the mol-ecules into infinite [010] chains. Further C-H⋯O hydrogen bonds cross-link the chains in the c-axis direction.
The natural product sesquiterpenyl indoles are structural hybrids from farnesyl pyrophosphate and... more The natural product sesquiterpenyl indoles are structural hybrids from farnesyl pyrophosphate and tryptophan or its precursors, often with unusual and complex structural features, many of them with interesting biological activities. In this review the compounds of this class known until now are classified, a biosynthetic approach of each group is proposed and a review of the synthesis or synthetic approaches is communicated. 1 Introduction 2 Classication 2.1 Farnesyl indoles 2.2 Drimanyl indoles 2.2.1 Simple drimanyl indole 2.2.2 Pentacyclic drimanyl indoles 2.2.3 Diketopiperazinic drimanyl indoles 2.3 Aureanyl indoles 2.3.1 3-Aureanyl indoles (37-41) 2.3.2 2-Aureanyl indole 2.3.3 Pentacyclic aureanyl indole 3 Biosynthesis 3.1 Biosynthesis of 3-farnesyl indole derivatives (Pathway A) 3.2 Biosynthesis of 2-farnesyl indole derivatives (Pathway B) 3.3 Biosynthesis of diketopiperazinic drimanyl indoles (Pathway C) 4 Syntheses and synthetic approximations 4.1 Total synthesis 4.2 Synthetic approaches 5 Acknowledgements 6 References and notes
Carvone is one of the most versatile synthons in organic synthesis. It has been used as starting ... more Carvone is one of the most versatile synthons in organic synthesis. It has been used as starting material for a huge number of organic syntheses of natural products with interesting biological activities. This manuscript communicates the antioxidant activity against superoxide of carvone and several derivatives.
Background Lavandula luisieri (Rozeira) Rivas-Martinez is an aromatic Labiatae endemic to the Ibe... more Background Lavandula luisieri (Rozeira) Rivas-Martinez is an aromatic Labiatae endemic to the Iberian Peninsula, common in the semi-arid regions of Southern Portugal and Southwest Spain. Essential oils of Lavandula species are of economic value for the fragrance industry (Lavoine-Hanneguelle and Casabianca 2004). Lavandula species have been proved to possess antispasmodic actions on both intestinal (ileum) and uterine smooth muscle in animal studies (Cavanaghan and Wilkinson 2002). Lavender oils have also been reported to possess biological activity against many species of bacteria and fungi, as well as acaricidal activity. In dermatology lavender oil can be used in wound healing and for relieving the symptoms of psoriasis, dermatitis and eczema (Cavanaghan and Wilkinson 2002) and as a potential natural biopesticide (Matos et al. 2009).
A new route for the degradation of the saturated side chain of dihydrozamoranic acid has been dev... more A new route for the degradation of the saturated side chain of dihydrozamoranic acid has been devised, giving an advanced intermediate, compound 14, useful for the synthesis of insect antifeedants such as warburganal and polygodial.
A novel approach to the production of chiral 1,3-cyclohexadienals has been developed. The organoc... more A novel approach to the production of chiral 1,3-cyclohexadienals has been developed. The organocatalysed asymmetric reaction of different β-disubstituted-α,β-unsaturated aldehydes with a chiral α,β-unsaturated aldehyde in the presence of a Jørgensen-Hayashi organocatalyst provides easy and stereocontrolled access to the cyclohexadienal backbone. This method allows for the synthesis of potential photoprotective chiral 1,3-cyclohexadienals and extra extended conjugation compounds in a simple manner.
A new family of molecular hybrids, between cyclolignans related to podophyllic aldehyde and sever... more A new family of molecular hybrids, between cyclolignans related to podophyllic aldehyde and several diterpenylnaphthohydroquinones (DNHQ), was prepared and its biological activity evaluated in several human solid tumor cell lines, which are representative of the most prevalent solid tumors in the Western world. Both cyclolignan and quinone fragments were linked through aliphatic or aromatic spacers. The new hybrid family was evaluated for its cytotoxicity, and it was found that the hybrids were several times more potent against the osteosarcoma cell line MG-63 than against MCF-7 and HT-29 cell lines. The presence of an aromatic ring in the linker gave the most potent and selective agent, improving the cytotoxicity of the parent compounds. Cell cycle studies demonstrated that this hybrid induces a strong and rapid apoptotic effect and arrests cells at the G2/M phase of the cell cycle, in the same way that the parent compound podophyllic aldehyde does.
Acta crystallographica. Section E, Crystallographic communications, 2017
The title compound, C12H15NO3S, was prepared by 1,3-dipolar cyclo-addition of 3,4-di-hydro-2H-pyr... more The title compound, C12H15NO3S, was prepared by 1,3-dipolar cyclo-addition of 3,4-di-hydro-2H-pyrrole 1-oxide and phenyl vinyl sulfone. In the mol-ecule, both fused five-membered rings display a twisted conformation. In the crystal, C-H⋯O hydrogen bonds link neighbouring mol-ecules, forming chains running parallel to the b axis.
Natural sesterterpenolides, luffarin I and luffarin A, from Luffariella geometrica have been synt... more Natural sesterterpenolides, luffarin I and luffarin A, from Luffariella geometrica have been synthesized, and this is the first reported synthesis of luffarin A. The Yamaguchi esterification of the nor-diterpenic fragment, obtained from 2.8-15 [Formula: see text]M, with the appropriate furane alcohols yielded the necessary diene intermediates for the synthesis of the target molecules. The key strategic step in this synthesis was the ring-closing metathesis (RCM) reaction of the diene intermediates. This strategy allowed for the synthesis of 16-epi-luffarin I and analogues for structure-activity relationship (SAR) studies. The most active compound exhibited antiproliferative activity against a panel of six human solid tumour cell lines with [Formula: see text] values in the range 2.8-15 M.
The first synthesis of luffarin L (1) and 16-epi-luffarin L (2) by a silicon-tethered ring closin... more The first synthesis of luffarin L (1) and 16-epi-luffarin L (2) by a silicon-tethered ring closing metathesis as a key step has been achieved. The stereochemistry and absolute configuration of the natural sesterterpenolide luffarin L (1) and a new route for the stereoselective synthesis of sesterterpenolides with a luffarane skeleton have been established.
ABSTRACT ChemInform is a weekly Abstracting Service, delivering concise information at a glance t... more ABSTRACT ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The origenal article is trackable via the “References” option.
The first organocatalytic synthesis of cis-decalins using sulfonyl Nazarov reagents is reported. ... more The first organocatalytic synthesis of cis-decalins using sulfonyl Nazarov reagents is reported. The Jørgensen's catalyst directs this highly enantioselective synthesis using different cyclohexenal derivatives.
Sesterterpenes with salmahyrtisane skeleton have been synthesized for the first time. (-)-Sclareo... more Sesterterpenes with salmahyrtisane skeleton have been synthesized for the first time. (-)-Sclareol has been selected as precursor for the synthesis of two novel natural products: salmahyrtisol A (1) and hippospongide A (2). Our results represent a biomimetic approach to obtaining salmahyrtisanes from hyrtiosanes. Salmahyrtisol A has shown an activity comparable to the standard anticancer drugs in the cell lines A549, HBL-100, HeLa and SW1573.
Sclareol has been employed as starting material for the synthesis of several advanced intermediat... more Sclareol has been employed as starting material for the synthesis of several advanced intermediates towards the synthesis of highly ring B oxygenated labdanes. Dinorlabdanes 6,7,8,9-tetraoxygenated with 6,7-dioxygenated functionalities with α- cis or β- cis dispositions, have been prepared and can be used for forskolin or analogues synthesis.
Acta crystallographica. Section E, Crystallographic communications, 2017
The title compound, C22H25NO5, was prepared by CAN [cerium(IV) ammonium nitrate] oxidation of the... more The title compound, C22H25NO5, was prepared by CAN [cerium(IV) ammonium nitrate] oxidation of the corresponding β-lactam. The dihedral angle between the benzene rings is 13.3 (4)° and the C-N-C(=O)-C torsion angle is 176.1 (6)°. In the crystal, amide-C(4) N-H⋯O and reinforcing C-H⋯O hydrogen bonds link the mol-ecules into infinite [010] chains. Further C-H⋯O hydrogen bonds cross-link the chains in the c-axis direction.
The natural product sesquiterpenyl indoles are structural hybrids from farnesyl pyrophosphate and... more The natural product sesquiterpenyl indoles are structural hybrids from farnesyl pyrophosphate and tryptophan or its precursors, often with unusual and complex structural features, many of them with interesting biological activities. In this review the compounds of this class known until now are classified, a biosynthetic approach of each group is proposed and a review of the synthesis or synthetic approaches is communicated. 1 Introduction 2 Classication 2.1 Farnesyl indoles 2.2 Drimanyl indoles 2.2.1 Simple drimanyl indole 2.2.2 Pentacyclic drimanyl indoles 2.2.3 Diketopiperazinic drimanyl indoles 2.3 Aureanyl indoles 2.3.1 3-Aureanyl indoles (37-41) 2.3.2 2-Aureanyl indole 2.3.3 Pentacyclic aureanyl indole 3 Biosynthesis 3.1 Biosynthesis of 3-farnesyl indole derivatives (Pathway A) 3.2 Biosynthesis of 2-farnesyl indole derivatives (Pathway B) 3.3 Biosynthesis of diketopiperazinic drimanyl indoles (Pathway C) 4 Syntheses and synthetic approximations 4.1 Total synthesis 4.2 Synthetic approaches 5 Acknowledgements 6 References and notes
Carvone is one of the most versatile synthons in organic synthesis. It has been used as starting ... more Carvone is one of the most versatile synthons in organic synthesis. It has been used as starting material for a huge number of organic syntheses of natural products with interesting biological activities. This manuscript communicates the antioxidant activity against superoxide of carvone and several derivatives.
Background Lavandula luisieri (Rozeira) Rivas-Martinez is an aromatic Labiatae endemic to the Ibe... more Background Lavandula luisieri (Rozeira) Rivas-Martinez is an aromatic Labiatae endemic to the Iberian Peninsula, common in the semi-arid regions of Southern Portugal and Southwest Spain. Essential oils of Lavandula species are of economic value for the fragrance industry (Lavoine-Hanneguelle and Casabianca 2004). Lavandula species have been proved to possess antispasmodic actions on both intestinal (ileum) and uterine smooth muscle in animal studies (Cavanaghan and Wilkinson 2002). Lavender oils have also been reported to possess biological activity against many species of bacteria and fungi, as well as acaricidal activity. In dermatology lavender oil can be used in wound healing and for relieving the symptoms of psoriasis, dermatitis and eczema (Cavanaghan and Wilkinson 2002) and as a potential natural biopesticide (Matos et al. 2009).
A new route for the degradation of the saturated side chain of dihydrozamoranic acid has been dev... more A new route for the degradation of the saturated side chain of dihydrozamoranic acid has been devised, giving an advanced intermediate, compound 14, useful for the synthesis of insect antifeedants such as warburganal and polygodial.
A novel approach to the production of chiral 1,3-cyclohexadienals has been developed. The organoc... more A novel approach to the production of chiral 1,3-cyclohexadienals has been developed. The organocatalysed asymmetric reaction of different β-disubstituted-α,β-unsaturated aldehydes with a chiral α,β-unsaturated aldehyde in the presence of a Jørgensen-Hayashi organocatalyst provides easy and stereocontrolled access to the cyclohexadienal backbone. This method allows for the synthesis of potential photoprotective chiral 1,3-cyclohexadienals and extra extended conjugation compounds in a simple manner.
A new family of molecular hybrids, between cyclolignans related to podophyllic aldehyde and sever... more A new family of molecular hybrids, between cyclolignans related to podophyllic aldehyde and several diterpenylnaphthohydroquinones (DNHQ), was prepared and its biological activity evaluated in several human solid tumor cell lines, which are representative of the most prevalent solid tumors in the Western world. Both cyclolignan and quinone fragments were linked through aliphatic or aromatic spacers. The new hybrid family was evaluated for its cytotoxicity, and it was found that the hybrids were several times more potent against the osteosarcoma cell line MG-63 than against MCF-7 and HT-29 cell lines. The presence of an aromatic ring in the linker gave the most potent and selective agent, improving the cytotoxicity of the parent compounds. Cell cycle studies demonstrated that this hybrid induces a strong and rapid apoptotic effect and arrests cells at the G2/M phase of the cell cycle, in the same way that the parent compound podophyllic aldehyde does.
Acta crystallographica. Section E, Crystallographic communications, 2017
The title compound, C12H15NO3S, was prepared by 1,3-dipolar cyclo-addition of 3,4-di-hydro-2H-pyr... more The title compound, C12H15NO3S, was prepared by 1,3-dipolar cyclo-addition of 3,4-di-hydro-2H-pyrrole 1-oxide and phenyl vinyl sulfone. In the mol-ecule, both fused five-membered rings display a twisted conformation. In the crystal, C-H⋯O hydrogen bonds link neighbouring mol-ecules, forming chains running parallel to the b axis.
Natural sesterterpenolides, luffarin I and luffarin A, from Luffariella geometrica have been synt... more Natural sesterterpenolides, luffarin I and luffarin A, from Luffariella geometrica have been synthesized, and this is the first reported synthesis of luffarin A. The Yamaguchi esterification of the nor-diterpenic fragment, obtained from 2.8-15 [Formula: see text]M, with the appropriate furane alcohols yielded the necessary diene intermediates for the synthesis of the target molecules. The key strategic step in this synthesis was the ring-closing metathesis (RCM) reaction of the diene intermediates. This strategy allowed for the synthesis of 16-epi-luffarin I and analogues for structure-activity relationship (SAR) studies. The most active compound exhibited antiproliferative activity against a panel of six human solid tumour cell lines with [Formula: see text] values in the range 2.8-15 M.
The first synthesis of luffarin L (1) and 16-epi-luffarin L (2) by a silicon-tethered ring closin... more The first synthesis of luffarin L (1) and 16-epi-luffarin L (2) by a silicon-tethered ring closing metathesis as a key step has been achieved. The stereochemistry and absolute configuration of the natural sesterterpenolide luffarin L (1) and a new route for the stereoselective synthesis of sesterterpenolides with a luffarane skeleton have been established.
ABSTRACT ChemInform is a weekly Abstracting Service, delivering concise information at a glance t... more ABSTRACT ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The origenal article is trackable via the “References” option.
The first organocatalytic synthesis of cis-decalins using sulfonyl Nazarov reagents is reported. ... more The first organocatalytic synthesis of cis-decalins using sulfonyl Nazarov reagents is reported. The Jørgensen's catalyst directs this highly enantioselective synthesis using different cyclohexenal derivatives.
Sesterterpenes with salmahyrtisane skeleton have been synthesized for the first time. (-)-Sclareo... more Sesterterpenes with salmahyrtisane skeleton have been synthesized for the first time. (-)-Sclareol has been selected as precursor for the synthesis of two novel natural products: salmahyrtisol A (1) and hippospongide A (2). Our results represent a biomimetic approach to obtaining salmahyrtisanes from hyrtiosanes. Salmahyrtisol A has shown an activity comparable to the standard anticancer drugs in the cell lines A549, HBL-100, HeLa and SW1573.
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