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The first total synthesis of cryptopyranmoscatones A3 and B4 has been accomplished from d-ribose or but-3-ynol. The key steps involved in the synthesis are oxa-Michael addition, highly diastereo­selective Brown allylation, and ring closing metathesis (RCM) and cross metathesis (CM) reactions.

The First total Synthesis of Brevipolide N and total Synthesis Brevipolide M have been accomplished from commercially available d -Mannitol. The key features of the syntheses are the use of Horner–Wadsworth–Emmons olefination, Noyori reduction, Acid catalyzed epoxide opening and Lindlars reaction.

An efficient approach for a reagent-based diversity-oriented synthesis (DOS) of novel fused spirooxindole scaffolds from oxindole enynes has been developed. The reaction involves a metal-catalyzed C-3 allylation/vinylation/homoallylation of N-substituted isatins which gives rise to the corresponding alcohols that can be converted into the required enynes. Further transformation to diverse complex molecular scaffolds proceeds via a subsequent ruthenium-catalyzed ring-closing enyne metathesis (RCEYM), or cobalt-catalyzed intramolecular Pauson–Khand (2+2+1) cyclization reaction (IPKR). This strategy provides a facile approach to various spirooxindole-vinyldihydropyrans/tetrahydrooxepines and spirocyclic fused cyclopentenones in good to excellent yields.

A series of novel 1,2,3-triazole and isoxazole-linked pyrazole derivatives have been synthesized from pyrazole and triazole/isoxazole scaffolds. The synthesized congeners were evaluated for their anti-proliferative efficacy in four cancer cell lines (MCF7, HEPG2, IMR32, and HELA). Majority of the compounds demonstrated potent cytotoxic activities, among them 4k and 4l showed significant cytotoxicity in all the tested cell lines.

The first total synthesis of Pestalotioprolide C and C7- epi -Pestalotioprolide C adopting Noyori asymmetric reduction, HWE Olefination and Shiina macrolactonization as the key steps has been described.

Synthesis of a silyl derivative of revised aglycone of marine anticancer macrolide Mandelalide A is described. The synthetic highlights include acid catalyzed epoxide opening, Chelation- controlled Grignard reaction, Still-Gennari olefination, Pd-catalyzed intramolecular alkoxycarbonylation, Kocien′ski-Julia olefination and Shiina macrolactonization as keysteps.

The first stereoselective total synthesis of a cytotoxic brevipolide M, which shares a pyrone framework bearing a tetrahydrofuran moiety and a cinnamate group with the readily available (-)-DET, is described. The key steps involved in the synthesis are the epoxide-opening, Brown's allylation, and the RCM reaction to install an α,β-unsaturated lactone ring and the inversion of the C-6' stereogenic hydroxyl group using the Mitsunobu reaction.

Total synthesis of spiroketal EBC-23 has been described by two divergent approaches from three simple building blocks. Gold-catalyzed cycloisomerization of alkynol and acid-mediated spirocyclization of diketalketone were successfully utilized to effect spiroketal formation. A Cu(I)-P(Cy)3-catalyzed protocol for the highly regio- and stereocontrolled hydroboration of internal propargylic alcohol was effectively applied toward the β-hydroxy ketone via vinylboronates.

The first total synthesis of phomopsolidone B and the total synthesis of phomopsolidone A have been achieved based on an olefin cross-metathesis approach starting from l -(+)-diethyl tartrate.

Revised structure of γ-lactone polyketide from Diaporthe sp. SXZ-19 and its C8-epimer were synthesized from TBS protected (S)-lactaldehyde and 2,3-O-cyclohexylidene- d -glyceraldehyde, which was derived from d -mannitol. The target γ-lactones were prepared via a common alkyne intermediate utilizing alkyne-aldehyde coupling reactions by changing the reaction conditions. In addition, Carreira and Ohira–Bestmann reactions were used as key steps to achieve the targets.

The total synthesis of sapinofuranones A,B and ent-sapinofuranones A,B and L-factor has been described. A series of novel 1,2,3-triazole-sapinofuranone hybrids were efficiently synthesized employing a click chemistry approach. These sapinofuranones and 1,2,3-triazole-sapinofuranone hybrids were further evaluated for their cytotoxic activity against four human cancer cell lines (A549, MDA-MB-231, DU145 and HepG2). Most of them revealed cytotoxic effects against cancer cells at the micromolar range. From a structure–activity relationship (SAR) perspective, it was noticed that the combination of triazole moiety to the lactone ring is playing modest role in exhibiting the cytotoxic effect. This is the first report on the synthesis and in vitro cytotoxic evaluation of 1,2,3-triazole-sapinofuranone hybrids.

A series of novel 1H-pyrrolo[2,3-d]pyrimidine-1,2,3-triazole derivatives have been synthesized in good to excellent yields. Through the copper-catalyzed azide-alkyne cycloaddition via reaction of 7-(prop-2-ynyl)-7H-pyrrolo[2,3-d]pyrimidine and aryl, heteroaryl and alkyl azides in the presence of CuSO4·5H2O and sodium ascorbate. These compounds were evaluated for their in vitro antimycobacterial activity against Mycobacterium tuberculosis H37Rv strain. Most of these pyrrolopyrimidine-triazole hybrids exhibited good anti tubercular activity. The antimycobacterial assay results showed that the minimum inhibitory concentration of compounds 4q and 4r were 0.78 µg/mL. The molecular docking results also had shown highest Moldock score for same compounds. These novel compounds exhibited good inhibition activities and further structure-activity studies of the derivatives had shown promising features to use in antitubercular therapy.

The stereoselective total synthesis of cryptomoscatone E1 has been accomplished. The strategy involves Carreira’s asymmetric alkynylation and olefin cross-metathesis reactions as key steps.

A stereoselective synthesis of the complete C1–C16 framework of tianchimycins A and B is described. Key transformations include Horner–Wadsworth–Emmons, Evans aldol, Gilman’s and stereoselective alkylation reactions.

The total synthesis of cryptomoscatone F1 has been accomplished for the first time. The strategy involves chelation-controlled allylation, the addition of alkylzinc to an aldehyde and olefin cross-metathesis reactions as key steps. a new route to a vinyl lactone was explored.

The first total synthesis of a naturally occurring styryl lactone, cryptopyranmoscatone A2 has been achieved from inexpensive and highly abundant D-ribose. The key features of the synthetic strategy are the utilization of oxa-Michael addition, asymmetric allylation and metathesis reactions.

The first total synthesis of pectinolides D and E and total synthesis of pectinolides A and C was achieved from a hitherto unknown common key building block prepared from readily available d -mannitol. Key reactions involved in the synthesis are Red-Al reduction of an epoxy alcohol, enantioselective Noyori reduction of ynones, aldehyde–alkyne coupling, and Still–Genari cis-olefination.

Total synthesis of the 14-membered macrolide Sch 725674 has been developed that is based on macrocyclic ring closure either by Yamaguchi or Shiina macrolactonization and the construction of the precursor seco acid by Pd(OH)2 transformation of primary propargyl alcohol/HWE olefination between two fragments is shown.

The first total synthesis of phomopsolidone A has been accomplished. The key features of the synthesis include the use of a stereoselective Grignard addition reaction, Still–Gennari and acid catalyzed lactonization reactions.

New polycyclic hexahydrobenzo[c]acridines were synthesized in excellent yields by intramolecular [4+2]-cycloaddition reactions of aldimines derived from aromatic amines and 2-(4-methylpent-3-en-1-yl)benzaldehyde in acetonitrile in the presence of 10 mol% of bismuth(III) chloride. The reaction is highly diastereoselective, giving cis-fused benzoacridine derivatives preferentially.

The first total synthesis of the natural saturated α-pyrone pectinolide F has been accomplished from inexpensive, commercially available ( S )-ethyl lactate and but-3-yn-1-ol. The salient features of the synthesis are 2,2,6,6-tetramethylpiperidin-1-oxyl (TEMPO)–[bis(acetoxy)iodo]benzene oxidation, Sharpless asymmetric dihydroxylation, Grignard reaction, and partial hydrogenation of the triple bond.

The stereoselective synthesis of (−)-synrotolide was achieved in high overall yield from d -(−)-ribose and 3-butyn-1-ol. The pivotal step in this approach is the selective deprotection of the acetonide group in the presence of acetate groups using TiCl 4 . Moreover, the biological activity of (−)-synrotolide was evaluated on HeLa, PANC 1, HepG2, and SK-N-SH cancer cell lines. The (−)-synrotolide selectively and potently inhibited the growth of PANC 1 cell line.

Stereoselective synthesis of the naturally occurring 6-membered lactone hyptolide 1 is described. The main feature of the synthesis is the utility of the hitherto unexplored alkyne fragment derived from commercially available 3-butyn-1-ol (homopropargylic alcohol).

The synthesis of C1–C8 and C9–C16 fragments of revised structure of (−)-lyngbouilloside is described starting from geraniol and D-malic acid.

An efficient one-pot synthesis of novel pyrido[2′,1′:2,3]imidazo[4,5-c]cinnoline derivatives has been achieved with moderate to good yields, with two C–N bond formations through C–H functionalization of 2-arylimidazo[1,2-a]pyridines. The reaction proceeds via C-3 regioselective hydrazination with diisopropyl azodicarboxylate followed by oxidative N-arylation mediated by phenyliodine(III) diacetate (PIDA) in trifluoroacetic acid by means of C–H functionalization to produce pyrido[2′,1′:2,3]imidazo[4,5-c]cinnolines. Other imidazoheterocycles such as 2-arylbenzo[d]imidazo[2,1-b]thiazoles, and 6-arylimidazo[2,1-b]thiazoles underwent similar transformations giving the corresponding cinnolines under transition metal-free and mild conditions.

The convergent synthesis of the C3–C11 and C12–C24 fragments of the iejimalides A–D is described. The C3–C11 fragment is obtained by a cross-metathesis reaction, while the C12–C24 fragment is derived from a Still–Gennari modified Horner–Wadsworth­–Emmons olefination.

The first stereoselective total synthesis of (–)-synrotolide has been realized by two different approaches, both starting from (S)-ethyl lactate. Both strategies used stereo- and regioselective epoxide opening with a nucleophile, aldehyde alkyne coupling and ring-closing metathesis as key steps. Judicious choice of reagents (CeCl3·7H2O and H2SiF6) for the chemoselective removal of protecting groups delivered the target molecule.

The first total synthesis of antimalarial (+)-cryptorigidifoliol A was accomplished by two different approaches in 6 and 5 steps with overall yields of 45% and 33%, respectively. Double asymmetric allylations and ring-closing metathesis reaction in route A, Prins, and RCM in route B were used as key steps.

The synthesis of phomopsolide B has been achieved using an olefin cross-metathesis (CM) reaction as key step. Two metathesis partners, enediol and 5-hydroxy vinyl lactone were prepared from l -ascorbic acid. This is the first report of using 5-hydroxy vinyl lactone in an olefin cross-metathesis reaction.

The first stereoselective total synthesis of synparvolide C has been accomplished. An acid-catalyzed epoxide ring-opening reaction and ring-closing metathesis (RCM) were used for the cyclic ether and δ-lactone formation, respectively, to furnish the core structure of the target molecule. These reactions along with a succession of functional group manipulations led to the preparation of the natural product. The spectral and analytical data were used to establish the absolute configuration.

Stereoselective syntheses of (−)-(1R,1′R,5′R,7′R)-1-hydroxy-exo-brevicomin (1) and (+)-exo-brevicomin (2) were accomplished from 3,4,6-tri-O-acetyl-D-glucal (5; Schemes 2 and 3). Chemoselective reduction, Grignard reaction, BartonMcCombie deoxygenation, and ketalization were used as key steps.

The stereoselective syntheses of synargentolide B and its three stereoisomers have been accomplished from L-(+)- and D-(–)-diethyl tartrates, D-ribose, and D-mannitol as chiral pool starting materials. The key step was a tandem ring-closing/cross-metathesis reaction in which lactone formation and fragment coupling were accomplished in one pot. The spectroscopic data of synthetic product 2c were in agreement with those reported for the natural product. Synargentolide B isolated by Rivett et al. and the compound isolated by Pereda-Miranda et al. are not diastereomers, but rather they are identical.

An efficient total synthesis of pectinolide H was achieved by using alkynylation, asymmetric reduction in the presence of a Corey–Bakshi–Shibata catalyst, and a Still–Gennari olefination as key steps.

An efficient synthesis of the C1–C19 segment of carolacton is described, starting from d -ribose, (–)-β-citronellene and a homopropargylic alcohol, and which employs a Nozaki–Hiyama–Kishi (NHK) coupling as the key step. Other important steps are cross-metathesis and Evans aldol reactions.

The first total synthesis of phomopsolidone A has been accomplished. The key features of the synthesis include the use of a stereoselective Grignard addition reaction, Still–Gennari and acid catalyzed lactonization reactions.

A diastereoselective synthesis of tetrahydro- and dihydro-pyrido[2,3-c]coumarin derivatives has been achieved via a one-pot three-component aza-Diels-Alder reaction of aromatic aldehydes, 3-aminocoumarin and dienophiles catalyzed by BiCl3. NOE studies proved that exo-isomers were obtained in all cases with high selectivity. The reaction proceeded at room temperature providing good yields of products as well as applicability on a wide range of substrates. Among all the synthesized derivatives, compounds 4i and 4k showed promising DPPH radical scavenging activity as compared to other tested derivatives.